Put thunk targets directly into loadable modules in static build

Put thunk targets directly into loadable modules in static build

gles2_thunks.cc, gles2_impl_thunks.cc, etc define symbols that should be
exported from loadable modules.  If these files are linked into a static
library and that static library is then linked into a loadable module,
the linker may or may not pull in the object files for the thunks
depending on if any symbols from that object file are referenced by
some other object file in the component.

This puts the thunks into a gypi that can be included directly into a
loadable module so the object files containing the thunks are on the
link line directly and make it into the final library.

R=erg@chromium.org

Committed: https://crrev.com/66d1d784036d8b7ab4889c46d0bdb87a9a264a9f
Cr-Commit-Position: refs/heads/master@{#292315}

[jamesr, 2014-08-27 19:04:40]

This fixes the thunk symbol missing error.  GN uses source_sets so it doesn't
have this problem.

[jamesr, 2014-08-27 19:05:53]

It's probably worth doing this for the system thunks as well, but that seems
less likely to break.

[DaveMoore, 2014-08-27 19:08:19]

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

[DaveMoore, 2014-08-27 19:08:19]

lgtm

[Elliot Glaysher, 2014-08-27 19:09:51]

lgtm

[jamesr, 2014-08-27 19:35:52]

The CQ bit was checked by jamesr@chromium.org

[commit-bot: I haz the power, 2014-08-27 19:36:28]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/509123003/1

[commit-bot: I haz the power, 2014-08-27 20:45:41]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-08-27 20:45:42]

Failed to commit the patch.

[jamesr, 2014-08-27 20:55:18]

On 2014/08/27 20:45:42, I haz the power (commit-bot) wrote:
> Failed to commit the patch.

Guessing this means the patch didn't apply?  That's pretty uninformative.  Will
rebase and try again...

[jamesr, 2014-08-27 20:56:10]

The CQ bit was checked by jamesr@chromium.org

[commit-bot: I haz the power, 2014-08-27 20:57:18]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jamesr@chromium.org/509123003/20001

[commit-bot: I haz the power, 2014-08-28 03:55:50]

Committed patchset #2 (id:20001) as bbed8a31a36c3449799a77fbca85bfe86c4564c8

[commit-bot: I haz the power, 2014-09-10 02:57:20]

Patchset 2 (id:??) landed as
https://crrev.com/66d1d784036d8b7ab4889c46d0bdb87a9a264a9f
Cr-Commit-Position: refs/heads/master@{#292315}