- Return the correct NaN when an invalid operation generates a NaN.
- When one or more operands are NaN, handle them as the processor
would, prioritising signalling NaNs and making them quiet.
- Fix fmadd and related instructions:
- Fnmadd is fma(-n, m, -a), not -fma(n, m, a).
- Some common libc implementations incorrectly implement fma for
zero results, so work around these cases.
- Replace some unreliable tests.
This patch also adds support for Default-NaN mode, since once all the
other work was done, it only required a couple of lines of code.
Default-NaN mode was used for an optimisation in ARM, and it should now
be possible to apply the same optimisation to A64.
BUG=
R=jochen@chromium.org
Review URL: https://codereview.chromium.org/199083005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19927 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Distinguish between context bound scripts (Script) and context unbound scripts
(UnboundScript).
- Add ScriptCompiler (which will later contain functions for async compilation).
This is a breaking change, in particular, Script::New no longer exists (it is
replaced by ScriptCompiler::CompileUnbound). Script::Compile remains as a
backwards-compatible shorthand for ScriptCompiler::Compile.
Passing CompilerOptions with produce_data_to_cache = true doesn't do anything
yet; the only way to generate the data to cache is the old preparsing API. (To
be fixed in the next version.)
This is a fixed version of https://codereview.chromium.org/186723005/
BUG=
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/199063003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19925 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Attempting to re-use the type feedback vector stored in the
SharedFunctionInfo turns out to be difficult among the various cases.
It will be much easier to do this when deferred type feedback processing
is removed, as is in the works.
Created bug v8:3212 to track re-introducing the optimization of reusing
the type vector on recompile before optimization.
The CL also brings back the type vector on the SharedFunctionInfo.
BUG=351257
LOG=Y
R=bmeurer@chromium.org, bmeuer@chromium.org
Review URL: https://codereview.chromium.org/199973004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19919 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Distinguish between context bound scripts (Script) and context unbound scripts
(UnboundScript).
- Add ScriptCompiler (which will later contain functions for async compilation).
This is a breaking change, in particular, Script::New no longer exists (it is
replaced by ScriptCompiler::CompileUnbound). Script::Compile remains as a
backwards-compatible shorthand for ScriptCompiler::Compile.
Passing CompilerOptions with produce_data_to_cache = true doesn't do anything
yet; the only way to generate the data to cache is the old preparsing API. (To
be fixed in the next version.)
BUG=
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/186723005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19881 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is preparatory work to get rid of UnsafePersistent in blink.
The previous version had to be reverted due to timeouts in win32/Debug: https://codereview.chromium.org/197173002/
The timeouts happened because the STL version on that platform contains sanity checking code which opens a 'debug window' in the GUI, patiently waiting for the user to click ok/cancel/somethirdoption. It turns out, the cause for that debug window was totally valid and the test had a use-after-free issue.
The 1st patch set is the code as before. The 2nd patch set contains the fix.
Related blink changes are here: https://codereview.chromium.org/180363004/
This patch is largely based on https://codereview.chromium.org/175503003/, with some methods added to support the blink change mentioned above.
BUG=
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/197263002
Patch from Daniel Vogelheim <vogelheim@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19873 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The tests were using different kind of constructs for achieving the same
thing. This makes refactoring the compilation API more difficult than it should
be.
cctest.h already contained helpers for compiling and running scripts, but they
were not used consistently.
For example, all these were used for running scripts:
v8::Script::Compile(v8_str("foo"))->Run();
v8::Script::Compile(v8::String::NewFromUtf8(isolate, "foo))->Run();
CompileRun(v8_str("foo"));
CompileRun(v8::String::NewFromUtf8(some_way_to_get_isolate(), "foo"));
v8::Local<v8::Script> script = any_of_the_above; script->Run();
Most of the tests just want to run a script (which is in const char*) and don't
care about how the v8::String is constructed or passed to the compiler API. Using
the helpers makes the test more readable and reduces boilerplate code which is
unrelated to what the test is testing.
R=dcarney@chromium.org
BUG=
Review URL: https://codereview.chromium.org/190503002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19753 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Notes:
- The regexp in the ParseObjectLiteralComment was wrong, made it less wrong (
it's still wrong since trailing commas are not required / allowed).
- Change in logic: In case we have "get somekeyword() { }", the "somekeyword"
was not logged as a symbol by PreParser and not expected in the preparser data
by Parser. This is unnecessary complication; in other contexts where keywords
are allowed as identifiers, they are logged as symbols (see
ParseIdentifierName).
BUG=v8:3126
LOG=N
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/173273006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19750 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Notes about a few TODOs handled in this patch:
* In ProfileEntryHookStub::Generate:
Stubs are always called with relocation.
* In CreateArrayDispatchOneArgument:
The branches to registers can't be conditional. We could use a jump table, but
there are only 6 different kinds so it is likely not worth it.
* In Builtins::Generate_StringConstructCode:
Rename the argc register (x0) after its meaning changes.
Remove a TODO: using a macro would not make the code clearer.
* In Generate_JSEntryTrampolineHelper:
Remove the TODO and raise an internal issue to investigate this.
* In Disassembler::SubstituteBranchTargetField:
Print the target address, but we don't have more info on the target.
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/185793002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19724 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When object is creating via native V8 API calls JS callstack is empty and the allocation is indistinguishable from say compiler allocations. This change adds a separate entry for such allocations.
Since FunctionInfo not necessarily corresponds to a heap object they are now referred to using their index in the list of all FunctionInfos.
BUG=chromium:277984
LOG=N
R=loislo@chromium.org, mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/177203002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19718 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This feature makes it possible to associate data with a script and get it back
when the script is compiled or when an event is handled. It was historically
used by Chromium Dev Tools, but not any more. It is not used by node.js.
Note: this has nothing to do with the preparse data, despite the confusing name.
The preparse data is passed as ScriptData*.
Note 2: This is the same as r19616 ( https://codereview.chromium.org/184403002/ )
with a unused variable fix in bootstrapper.cc.
R=svenpanne@chromium.org
BUG=
Review URL: https://codereview.chromium.org/185533014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19702 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This adds a pointer to the shared function info into deoptimization data of an optimized code. Whenever the code is deoptimized, it clears the cache in the shared function info.
This fixes the problem when the optimized function dies in new space GC before the code is deoptimized due to code dependency and before the optimized code cache is cleared in old space GC (see mjsunit/regress/regress-343609.js).
This partially reverts r19603 because we need to be able to evict specific code from the optimized code cache.
BUG=343609
LOG=Y
TEST=mjsunit/regress/regress-343609.js
R=yangguo@chromium.org
Review URL: https://codereview.chromium.org/184923002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19635 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This feature makes it possible to associate data with a script and get it back
when the script is compiled or when an event is handled. It was historically
used by Chromium Dev Tools, but not any more. It is not used by node.js.
Note: this has nothing to do with the preparse data, despite the confusing name.
The preparse data is passed as ScriptData*.
R=svenpanne@chromium.org
BUG=
Review URL: https://codereview.chromium.org/184403002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19616 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Preparsing is always maximally lazy (every function that can be lazy is preparsed
lazily), but Parser has more complicated laziness logic.
If we're going to parse eagerly, and we have preparse data from lazy preparsing,
we're gonna have a bad time. The symbol stream won't contain symbols inside lazy
functions, and when the Parser parses them eagerly, it will consume symbols from
the symbol stream, and everything will go wrong.
This bug was hidden because the symbol cache was not used for real (see
https://codereview.chromium.org/172753002/ ).
R=ulan@chromium.org
BUG=346207
LOG=Y
Review URL: https://codereview.chromium.org/177973002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19532 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The Parser never used the symbol stream produced by the PreParser for anything
useful, due to a bug introduced 3.5 years ago by
https://codereview.chromium.org/3356010/diff/7001/src/parser.cc.
The bug is that calling Initialize on symbol_cache_ doesn't change its
length. So the length remains 0, and the "if" in Parser::LookupSymbol is always
true, and Parser::LookupCachedSymbol is never called and symbol_cache_ never
filled.
This bug also masked a bug that the symbol stream produced by PreParser doesn't
match what Parser wants to consume. The repro case is the following:
var myo = {if: 4}; print(myo.if);
PreParser doesn't log a symbol for the first "if", but in the corresponding
place, Parser consumes one symbol from the symbol stream. Since the consumed
symbols were never really used, this mismatch went unnoticed.
This CL also fixes that bug.
BUG=
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/172753002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19505 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Refresh the implementation of Symbols to catch up with what the
specification now mandates:
* The global Symbol() function manufactures new Symbol values,
optionally with a string description attached.
* Invoking Symbol() as a constructor will now throw.
* ToString() over Symbol values still throws, and
Object.prototype.toString() stringifies like before.
* A Symbol value is wrapped in a Symbol object either implicitly if
it is the receiver, or explicitly done via Object(symbolValue) or
(new Object(symbolValue).)
* The Symbol.prototype.toString() method no longer throws on Symbol
wrapper objects (nor Symbol values.) Ditto for Symbol.prototype.valueOf().
* Symbol.prototype.toString() stringifies as "Symbol("<description>"),
valueOf() returns the wrapper's Symbol value.
* ToPrimitive() over Symbol wrapper objects now throws.
Overall, this provides a stricter separation between Symbol values and
wrapper objects than before, and the explicit fetching out of the
description (nee name) via the "name" property is no longer supported
(by the spec nor the implementation.)
Adjusted existing Symbol test files to fit current, adding some extra
tests for new/changed behavior.
LOG=N
R=arv@chromium.org, rossberg@chromium.org, arv, rossberg
BUG=v8:3053
Review URL: https://codereview.chromium.org/118553003
Patch from Sigbjorn Finne <sigbjornf@opera.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19490 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This addresses several TODOs:
- Push and Pop requests can be queued up so that arrays of Registers
can be pushed efficiently, with just one PrepareForPush/Pop.
- PushMultipleTimes now takes an Operand. This allows variable-length
arguments arrays to be initialized, for example.
- A NoUseRealAbortsScope has been added to Abort so that
AssertStackConsistency can be called from PrepareForPush without
introducing infinite recursion.
BUG=
R=rmcilroy@chromium.org, ulan@chromium.org
Review URL: https://codereview.chromium.org/170623002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19474 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Code generation would fail when assembling a branch to a label that is bound
outside the immediate range of the instruction. A64 is sensitive to this, as the
various branching instructions have different ranges, going down to +-32KB for
TBZ/TBNZ. The MacroAssembler is augmented to handle branches to targets that
may exceed the immediate range of instructions.
When branching backward to a label exceeding the instruction range, the
MacroAssembler can simply tweak the generated code to use an unconditional
branch with a longer range. For example instead of
B(cond, &label);
the MacroAssembler can generate:
b(InvertCondition(cond), &done);
b(&label);
bind(&done);
Since the target is not known when the branch is emitted, forward branches uses
a different mechanism. The MacroAssembler keeps track of forward branches to
unbound labels. When the code generation approaches the end of the range of a
branch, a veneer is generated for the branch.
BUG=v8:3148
LOG=Y
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/169893002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19444 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Notes:
- We use simple recursion to keep track of how many "new" operators we have seen
and where.
- This makes the self-baked stack class PositionStack in parser.cc unnecessary.
- Now the logic is also unified between Parser and PreParser.
- This is a fixed version of r19386.
R=ulan@chromium.org
BUG=v8:3126
LOG=N
Review URL: https://codereview.chromium.org/168583008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19417 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This addresses several TODOs:
- Push and Pop requests can be queued up so that arrays of Registers
can be pushed efficiently, with just one PrepareForPush/Pop.
- PushMultipleTimes now takes an Operand. This allows variable-length
arguments arrays to be initialized, for example.
- A NoUseRealAbortsScope has been added to Abort so that
AssertStackConsistency can be called from PrepareForPush without
introducing infinite recursion.
BUG=
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/169533002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19403 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Notes:
- We use simple recursion to keep track of how many "new" operators we have seen
and where.
- This makes the self-baked stack class PositionStack in parser.cc unnecessary.
- Now the logic is also unified between Parser and PreParser.
- It might have been a copy-paste artifact (ParseLeftHandSideExpression ->
ParseMemberWithNewPrefixesExpression) that the logic was so complicated
before.
R=ulan@chromium.org
BUG=v8:3126
LOG=N
Review URL: https://codereview.chromium.org/166943002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19386 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Notes:
- To be able to move the recursive descent functions to ParserBase one at a
time, we temporarily need routing functions from traits to Parser/PreParser,
since the recursive descent functions form a cyclic structure.
- PreParser used to always allow intrinsic syntax. After this CL, it depends on
allow_natives_syntax() which was already in ParserBase.
- This CL also decouples (Pre)ParserTraits better from (Pre)Parser, passing more
information as parameters, so that the Traits don't need to get it from
(Pre)Parser.
R=ulan@chromium.org
BUG=v8:3126
LOG=N
Review URL: https://codereview.chromium.org/163333003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19374 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This patch generalizes Object.observe callbacks and promise resolution into a FIFO queue called a "microtask queue".
It also exposes new V8 API which exposes the microtask queue to the embedder. In particular, it allows the embedder to
-schedule a microtask (EnqueueExternalMicrotask)
-run the microtask queue (RunMicrotasks)
-control whether the microtask queue is run automatically within V8 when the last script exits (SetAutorunMicrotasks).
R=dcarney@chromium.org, rossberg@chromium.org, dcarney, rossberg, svenpanne
BUG=
Review URL: https://codereview.chromium.org/154283002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19344 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
(Second try, with fixes. First try: https://codereview.chromium.org/149913006/ )
The long-term goal is to move all recursive descent functions from Parser and
PreParser into ParserBase, but first they need to be unified.
Notes:
- The functions moved in this CL: ParseIdentifier, ParseIdentifierName,
ParseIdentifierNameOrGetOrSet, ParseIdentifierOrStrictReservedWord.
- IOW, this CL removes Parser::ParseIdentifier and PreParser::ParseIdentifier
and adds ParserBase::ParseIdentifier, etc.
- Error reporting used to require virtual funcs; now error reporting is moved to
the Traits too, and ParserBase no longer needs to be virtual.
- I had to move PreParser::Identifier out of the PreParser class, because
otherwise PreParserTraits cannot use it in a typedef.
BUG=v8:3126
LOG=N
R=mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/158913003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19265 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The long-term goal is to move all recursive descent functions from Parser and
PreParser into ParserBase, but first they need to be unified.
Notes:
- The functions moved in this CL: ParseIdentifier, ParseIdentifierName,
ParseIdentifierNameOrGetOrSet, ParseIdentifierOrStrictReservedWord.
- IOW, this CL removes Parser::ParseIdentifier and PreParser::ParseIdentifier
and adds ParserBase::ParseIdentifier, etc.
- Error reporting used to require virtual funcs; now error reporting is moved to
the Traits too, and ParserBase no longer needs to be virtual.
- I had to move PreParser::Identifier out of the PreParser class, because
otherwise PreParserTraits cannot use it in a typedef.
BUG=v8:3126
LOG=N
R=mstarzinger@chromium.org
Review URL: https://codereview.chromium.org/149913006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19230 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
ES6 makes the Function object properties "length" and "name"
configurable; switch the implementation over to follow that.
Doing so exposed a problem in the handling of non-writable, but
configurable properties backed by foreign callback accessors
internally. As an optimization, if such an accessor property is
re-defined with a new value, its setter was passed the new value
directly, keeping the property as an accessor property. However, this
is not correct should the property be non-writable, as its setter will
then simply ignore the updated value. Adjust the enabling logic for
this optimization accordingly, along with adding a test.
LOG=N
R=rossberg@chromium.org, rossberg
BUG=v8:3045
Review URL: https://codereview.chromium.org/116083006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19200 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Still relevant parts of the original commit message:
Unify paren handling in Parser and PreParser.
It is only needed in (Pre)Parser::ParseExpressionOrLabelledStatement for not
recognizing parenthesized identifiers as labels and in
(Pre)Parser::ParseSourceElements for not recognizing a parenthesized string as
directive prologue.
Parser Expressions don't keep track of whether they're parenthesized, so
PreParser Expressions shouldn't either.
BUG=3126
LOG=N
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/148323011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19153 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
It is only needed in (Pre)Parser::ParseExpressionOrLabelledStatement for not
recognizing parenthesized identifiers as labels and in
(Pre)Parser::ParseSourceElements for not recognizing a parenthesized string as
directive prologue.
Parser Expressions don't keep track of whether they're parenthesized, so
PreParser Expressions shouldn't either.
In addition, add helper funcs for checking if an Expression is identifier or a
given identifier. (PreParser Expressions can do this.)
BUG=3126
LOG=N
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/150103004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19140 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
We need a way to assert that for a given source code snippet, an error *is*
produced or *is not* produced. Otherwise we might accidentally create new
errors or start accepting code which was previously not accepted. Just checking
that Parser and PreParser produce the same result doesn't cut it.
BUG=3126
LOG=N
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/154243005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19107 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is what I think is a better solution to the "external strings in
old pointer space" problem. Basically, it is an issue because GC scans
all fields of objects in old pointer space and if the cached address
of the backing store is unaligned, it looks like a heap object, boom.
The solution here is to use short external strings when we externalize
a string in old pointer space, and when the address is unaligned.
Short external strings don't cache the address, so GC has no issues.
BUG=268686
LOG=Y
R=dcarney@chromium.org
Review URL: https://codereview.chromium.org/146183006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19093 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In addition:
- Fix: PreParser used to report an unexpected token one token too late when
ParsePrimaryExpression failed.
- Unified identifier handling (PreParser::GetIdentifier is now like Parser::GetIdentifier).
- Fix: PreParser used to produce "unexpected_token YIELD" errors when Parser
produced "unexpected_token_identifier"; fixed PreParser to match Parser.
BUG=3126
LOG=N
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/151103006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19082 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This contains the following fixes:
- We had strict_reserved_word and unexpected_strict_reserved, which one to use
was totally mixed in Parser and PreParser. Removed strict_reserved_word.
- When we saw a strict future reserved word when expecting something completely
different (such as "(" in "function foo interface"), Parser reports unexpected
identifier, whereas PreParser used to report unexpected strict reserved
word. Fixed PreParser to report unexpected identifier too.
- Unified parser and preparser error locations when the name of a function is a
strict reserved word. Now both point to the name.
BUG=3126
LOG=N
R=ulan@chromium.org
Review URL: https://codereview.chromium.org/149253010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19067 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This patch makes String::WriteUtf8 replace invalid code points (i.e. unmatched
surrogates) with the unicode replacement character when REPLACE_INVALID_UTF8 is
set. This is done to avoid creating invalid UTF-8 output which can lead to
compatibility issues with software requiring valid UTF-8 inputs (e.g. the
WebSocket protocol requires valid UTF-8 and terminates connections when invalid
UTF-8 is encountered).
R=dcarney@chromium.org
BUG=
Review URL: https://codereview.chromium.org/121173009
Patch from Felix Geisendörfer <haimuiba@gmail.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18683 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When invoking a setter callback for a property using
JSObject::SetPropertyWithCallback(),the callback arguments includes
a correct pair of receiver and holder objects.
Such a pair of _possibly different_ arguments (receiver, holder) must
also be supplied when invoking the same setter callback from JITed
code, when the setter is invoked through the StoreCallbackProperty
stub.
An example where this matters are the accessor properties kept on the
global scope of Worker (i.e., properties kept on the global object
itself, and not on its prototype.) Conflating the receiver with the
holder leads to general confusion when attempting to fetch out the
wrapper object.
LOG=N
R=dcarney@chromium.org, dcarney
BUG=239669
Review URL: https://codereview.chromium.org/139263008
Patch from Sigbjorn Finne <sigbjornf@opera.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18658 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
