ResourceProvider should be able to avoid allocating immutable textures.

ResourceProvider should be able to avoid allocating immutable textures.

copyTexImage2D will fail when called on a texture having immutable
storage, allocated using texStorage2DEXT.
I encountered this problem while working on mix-blend-mode in cc:
http://crrev.com/23455060#msg51.

This problem is valid for background filters as well. Background filters
unittests pass because the test framework uses mesa, which does not
support texture storage. I couldn't create cc_unittests for the same
reason.
Texture storage currently is supported on windows using angle by
default.


BUG=243223
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=236482

[rosca, 2013-11-20 21:37:12]

Please review.

[danakj, 2013-11-21 00:20:40]

Thank you for the test and explanation, and breaking this out. LTM

https://codereview.chromium.org/79603002/diff/1/cc/output/gl_renderer.cc
File cc/output/gl_renderer.cc (right):

https://codereview.chromium.org/79603002/diff/1/cc/output/gl_renderer.cc#newc...
cc/output/gl_renderer.cc:619: // The TextureUsageFramebuffer hint makes
ResourceProvider to avoid immutable
s/to avoid/avoid/

[danakj, 2013-11-21 00:20:49]

Er, LGTM I mean!

[commit-bot: I haz the power, 2013-11-21 06:41:38]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rosca@adobe.com/79603002/70001

[commit-bot: I haz the power, 2013-11-21 09:55:50]

Change committed as 236482