Enable KHR_parallel_shader_compile extension

This updates the khronos GL headers to incorporate the missing
API declarations for the extension.
This also regenerates the ui/gl binding accordingly.

BUG=849576

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: I2ce5b91e7459f518593924b55621896ed4825510
Reviewed-on: https://chromium-review.googlesource.com/1201353
Reviewed-by: Antoine Labour <[email protected]>
Reviewed-by: Kenneth Russell <[email protected]>
Commit-Queue: Jie A Chen <[email protected]>
Cr-Commit-Position: refs/heads/master@{#590900}
40 files changed