Implement Harmony semantics for typeof null (behind a flag).

Implement Harmony semantics for typeof null (behind a flag).

Harmony is intended to make typeof null === "null". This may
break existing programs. Implementing it will allow us to run
some tests on the actual web.

R=kmillikin@chromium.org
BUG=
TEST=

Committed: http://code.google.com/p/v8/source/detail?r=8876

[Jakob Kummerow, 2011-08-09 11:14:43]

(fixed typo in Kevin's email address.)

[Kevin Millikin (Chromium), 2011-08-10 09:52:21]

LGTM.

http://codereview.chromium.org/7598030/diff/1/src/runtime.cc
File src/runtime.cc (right):

http://codereview.chromium.org/7598030/diff/1/src/runtime.cc#newcode4857
src/runtime.cc:4857: : isolate->heap()->object_symbol();
Normal V8 style seems to be to break like this:

return FLAG_harmony_typeof
    ? isolate->heap()->null_symbol()
    : isolate->heap()->object_symbol();

Avoids running away to the right at the cost of one more line.

http://codereview.chromium.org/7598030/diff/1/test/mjsunit/harmony/typeof.js
File test/mjsunit/harmony/typeof.js (right):

http://codereview.chromium.org/7598030/diff/1/test/mjsunit/harmony/typeof.js#...
test/mjsunit/harmony/typeof.js:1: // Flags: --harmony-typeof
We usually put the flags below the copyright notice.

And update the year in the copyright notice :)

[rossberg, 2011-08-10 12:01:35]

http://codereview.chromium.org/7598030/diff/1/src/runtime.cc
File src/runtime.cc (right):

http://codereview.chromium.org/7598030/diff/1/src/runtime.cc#newcode4857
src/runtime.cc:4857: : isolate->heap()->object_symbol();
On 2011/08/10 09:52:21, Kevin Millikin wrote:
> Normal V8 style seems to be to break like this:
> 
> return FLAG_harmony_typeof
>     ? isolate->heap()->null_symbol()
>     : isolate->heap()->object_symbol();
> 
> Avoids running away to the right at the cost of one more line.

Done.

http://codereview.chromium.org/7598030/diff/1/test/mjsunit/harmony/typeof.js
File test/mjsunit/harmony/typeof.js (right):

http://codereview.chromium.org/7598030/diff/1/test/mjsunit/harmony/typeof.js#...
test/mjsunit/harmony/typeof.js:1: // Flags: --harmony-typeof
On 2011/08/10 09:52:21, Kevin Millikin wrote:
> We usually put the flags below the copyright notice.
> 
> And update the year in the copyright notice :)

Done.