[bindings] Bindings should only support the prescribed types for constants.

[bindings] Bindings should only support the prescribed types for constants.

Specification at https://heycam.github.io/webidl/#idl-constants mentions the constants
should be defined as:

  const type identifier = value;

whereas the |type| is mentioned as:

  The type of a constant (matching ConstType) must not be any type other than a primitive
  type or a nullable primitive type

And string literals are not treated as primitive types. Hence we should remove the support
for having a constant like:

  const DOMString hello = "world";

BUG=469961
R=haraken@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=201278

[vivekg, 2015-08-26 13:47:16]

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

[vivekg, 2015-08-26 13:47:17]

The usage of DOMString as constant is treated as error in FF as per [1]

Also removing this support gets us the following size table:

+------------+-----------+---------+---------+
|            | text      | data    | bss     |
+------------+-----------+---------+---------+
| W/o Patch  | 103215908 | 4922016 | 1058308 |
+------------+-----------+---------+---------+
| With Patch | 103215882 | 4912352 | 1058308 |
+------------+-----------+---------+---------+

[1]
http://lxr.mozilla.org/mozilla-central/source/testing/web-platform/tests/reso...

[vivekg, 2015-08-26 13:50:13]

The CQ bit was checked by vivekg@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-08-26 13:50:27]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1315663004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1315663004/1

[vivekg, 2015-08-26 13:52:19]

The CQ bit was unchecked by vivekg@chromium.org

[haraken, 2015-08-26 23:22:00]

LGTM

[vivekg, 2015-08-27 00:29:41]

The CQ bit was checked by vivekg@chromium.org

[commit-bot: I haz the power, 2015-08-27 00:29:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1315663004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1315663004/1

[commit-bot: I haz the power, 2015-08-27 02:31:54]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=201278