commit 0500571c0a41d977f64653eeaed4809351205a35
author yizhou.jiang <yizhou.jiang@intel.com> Mon Oct 24 04:27:04 2016
committer Commit bot <commit-bot@chromium.org> Mon Oct 24 04:29:57 2016
tree 86af2ba9795dfcf3abba3017d3820ccc81ef60b3
parent 391fa63bcefd25b35addf678356828dded5ae71e

optimize precision for conversion from srgb to linear

Convertion from sRGB to 8-bit linear is going to reduce the
precision of the texture, and the downsampling will do the
same thing. We should set texture internalformat to rgba32f
to optimize precision.

BUG=634519
TEST=conformance2/textures/misc/tex-srgb-mipmap.html
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2420813002
Cr-Commit-Position: refs/heads/master@{#427014}