Simplify language feature management.

Simplify language feature management.

R=rossberg@chromium.org
BUG=v8:3640
LOG=N

Committed: https://code.google.com/p/v8/source/detail?r=24743

[Dmitry Lomov (no reviews), 2014-10-20 09:28:05]

This is work in progress, in particular:
- Flag for shipped features is still exposed
- No support for experimental native functions

[Dmitry Lomov (no reviews), 2014-10-20 12:57:43]

This is now ready for review. 
Review patch set 7, patch set 8 is an example of shipping a feature (changes
only in flag-definitions.h and v8.gyp)

[rossberg, 2014-10-20 13:14:27]

LGTM with comment

https://codereview.chromium.org/642233003/diff/140001/src/flag-definitions.h
File src/flag-definitions.h (right):

https://codereview.chromium.org/642233003/diff/140001/src/flag-definitions.h#...
src/flag-definitions.h:158: V(scoping, "harmony block scoping")                 
   \
I'd prefer not to strip the harmony_ prefix from the flag name here. It can be
confusing when you try to grep for flags.

https://codereview.chromium.org/642233003/diff/140001/test/mjsunit/debug-scri...
File test/mjsunit/debug-script.js (right):

https://codereview.chromium.org/642233003/diff/140001/test/mjsunit/debug-scri...
test/mjsunit/debug-script.js:28: // Flags: --expose-debug-as debug --expose-gc
--send-idle-notification --allow-natives-syntax
Line length

[Dmitry Lomov (no reviews), 2014-10-20 13:32:54]

Comments addressed, landing.

https://codereview.chromium.org/642233003/diff/140001/src/flag-definitions.h
File src/flag-definitions.h (right):

https://codereview.chromium.org/642233003/diff/140001/src/flag-definitions.h#...
src/flag-definitions.h:158: V(scoping, "harmony block scoping")                 
   \
On 2014/10/20 13:14:27, rossberg wrote:
> I'd prefer not to strip the harmony_ prefix from the flag name here. It can be
> confusing when you try to grep for flags.

Done.

https://codereview.chromium.org/642233003/diff/140001/test/mjsunit/debug-scri...
File test/mjsunit/debug-script.js (right):

https://codereview.chromium.org/642233003/diff/140001/test/mjsunit/debug-scri...
test/mjsunit/debug-script.js:28: // Flags: --expose-debug-as debug --expose-gc
--send-idle-notification --allow-natives-syntax
On 2014/10/20 13:14:27, rossberg wrote:
> Line length

Done.

[Dmitry Lomov (no reviews), 2014-10-20 13:33:51]

Committed patchset #9 (id:160001) manually as 24743 (presubmit successful).

[adamk, 2014-10-20 17:44:29]

adamk@chromium.org changed reviewers:
+ adamk@chromium.org

[adamk, 2014-10-20 17:44:30]

Am I reading this patch right that it's simply refactoring, and not yet getting
us to a place where we can enable-by-default features that have experimental
natives?