- This fixes all ViewportTest.* and MipmapTest.*
- Tests left to fix in end2end:
	- BlitFramebuffer*
	- MaxTextureSizeTest.*
	- PointSpritesTest.*

Every other test in angle_end2end_tests are working.

Bug: angleproject:2673
Change-Id: I162083bc847c15fa5490ab524ad4c22747d232ea
Reviewed-on: https://chromium-review.googlesource.com/1126333
Commit-Queue: Luc Ferron <lucferron@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>