Reintroduce duplicate identifier detection in preparser.

Reintroduce duplicate identifier detection in preparser.

Duplicate identifier detection must be an early syntax error in strict code,
so errors in otherwise lazily compiled functions must be caught in the
preparser.

Originally introduced in r8541 and reverted in r8542.
Now really compiles on Windows.

Committed: http://code.google.com/p/v8/source/detail?r=9172

[Rico, 2011-09-07 07:39:05]

LGTM (as discussed offline, this is very similar to 8541 except code moved from 
platform.h and platform-win32.h to win32-math.*)

[Rico, 2011-09-07 11:51:31]

Still LGTM

http://codereview.chromium.org/7782023/diff/3003/src/globals.h
File src/globals.h (right):

http://codereview.chromium.org/7782023/diff/3003/src/globals.h#newcode45
src/globals.h:45: #if __GNUC_VERSION_FOR_INFTY__ >= 29600 &&
__GNUC_VERSION_FOR_INFTY__ < 40100
Chromium requires GCC 4.2 can't we remove this and do the same?

[Lasse Reichstein, 2011-09-07 11:59:14]

http://codereview.chromium.org/7782023/diff/3003/src/globals.h
File src/globals.h (right):

http://codereview.chromium.org/7782023/diff/3003/src/globals.h#newcode45
src/globals.h:45: #if __GNUC_VERSION_FOR_INFTY__ >= 29600 &&
__GNUC_VERSION_FOR_INFTY__ < 40100
We probably could, but I'd say that's an executive decision :)