Switch shader_translator from khronos GL to ui/gl

In jumbo experiments build targets using both ui/gl+mesa and khronos
at the same time fail to compile because the two GL libraries
declare the same constants and functions.

This happened in gpu/command_buffer/service because ShaderTranslator
used khronos GL when it should have been using ui/gl. This patch switches
that code over to ui/gl.

Bug: 864986
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I522243374eaf0416df58d84e20585c11aef3de32
Reviewed-on: https://chromium-review.googlesource.com/1145306
Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: Daniel Bratell <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#577236}
4 files changed