cc: Move FallbackFence implementation from GLRenderer to ResourceProvider.

cc: Move FallbackFence implementation from GLRenderer to ResourceProvider.

This allows us to use the same fallback fence for CopyResource
implementation as the GLRenderer, which means the 1-copy
rasterizer can be used even when CHROMIUM_sync_query support
is missing.

CHROMIUM_sync_query is expected to be supported everywhere
but this is useful in rare cases where it's been blacklisted.
While software compositing might be better in those cases,
having the option to use hardware compositing is valuable.

The frequency at which we check busy resources in the 1-copy
rasterizer is also reduced to make the performance penalty
of using the fallback fence less severe.

BUG=406404
Committed: https://crrev.com/9bc50696509edce28d25653b19eef51b099a3781
Cr-Commit-Position: refs/heads/master@{#301878}

[reveman, 2014-10-29 04:55:49]

reveman@chromium.org changed reviewers:
+ piman@chromium.org

[piman, 2014-10-29 17:27:24]

lgtm

[reveman, 2014-10-29 17:28:15]

The CQ bit was checked by reveman@chromium.org

[commit-bot: I haz the power, 2014-10-29 17:29:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/689463003/20001

[commit-bot: I haz the power, 2014-10-29 18:19:29]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2014-10-29 18:20:09]

Patchset 2 (id:??) landed as
https://crrev.com/9bc50696509edce28d25653b19eef51b099a3781
Cr-Commit-Position: refs/heads/master@{#301878}