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
We use foreign callbacks to make some properties shadow internal values
but still behave as data properties from within JavaScript. This means
when a value is passed to Object.defineProperty() on such a property,
it should update the internal value instead of redefinind the property
and destroying the shadowing.
R=rossberg@chromium.org
BUG=v8:1530
TEST=mjsunit/regress/regress-1530,test262/S15.3.3.1_A4
Review URL: http://codereview.chromium.org/8996008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10279 ce2b1a6d-e550-0410-aec6-3dcde31c8c00