Plumbing: Cache the resize callback so that we can call it later.

Plumbing: Cache the resize callback so that we can call it later.

I am working towards having two surfaces that the GpuScheduler alternates between on SwapBuffers. Each surface should be resized once it is the backbuffer (via SwapBuffers). By caching the resize callback, I can (a) resize of the backbuffer immediately when the callback is initiated from the GLES2Decoder and (b) resize the frontbuffer once it becomes the backbuffer after a SwapBuffers. 

BUG=none
TEST=none (should be no-op on all platforms)

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=88327

[jonathan.backer, 2011-06-07 15:43:41]

I need to change the flow slightly for my EGLImage transport work. This is a
no-op on all platforms, but gives me a hook into the resize mechanism.

[apatrick_chromium, 2011-06-07 18:11:46]

LGTM