On 'debugger' statement, if anything in debugger calls 'EnsureDebugInfo'
on a function, EnsureDebugInfo would compile and substitute code without
debug break slots. This causes weird behavior later when stepping fails
to work (see added test as an example).
This fix is to make sure the debugger is prepared for breakpoints in
that case as well.
Also adds extra testing for bug 468661.
R=yangguo@chromium.org,yurys@chromium.orh
BUG=v8:3990,chromium:468661
LOG=N
Review URL: https://codereview.chromium.org/1032353002
Cr-Commit-Position: refs/heads/master@{#27502}
The root cause for the bug is that the positions assigned to desugared
code was inconsistent with the source ranges of block scopes.
Since the fact that the position is assigned causes the debugger to
break at the parser-generated statement, the fix is to remove positions
from those nodes that we do not want to break on.
The CL also teaches Hydrogen to tolerate these cases.
R=adamk@chromium.org,rossberg@chromium.org
BUG=chromium:468661
LOG=Y
Review URL: https://codereview.chromium.org/1032653002
Cr-Commit-Position: refs/heads/master@{#27424}
