Use GLES2Interface in GLRenderer

This ports GLRenderer to (almost) exclusively use GLES2Interface as the
context type instead of WebGraphicsContext3D. The remaining users within
gl_renderer.cc are being addressed in parallel patches. Many callers
outside of gl_renderer.cc still use the WebGraphicsContext3D type, so
GLRenderer still exposes a pointer of that type. They'll be migrated piece
by piece.

Since this patch changes the line length of many lines due to changing the
context pointer type from "context_" to "gl_" and changing the length
of some of the context functions, I've clang-format'd the whole file.

BUG=181120
R=danakj@chromium.org

Review URL: https://codereview.chromium.org/105553003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240041 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 240041