Roll WebGL 7ca87fb..6d2f3f4

https://chromium.googlesource.com/external/khronosgroup/webgl.git/+log/7ca87fb..6d2f3f4

Tbr: kainino@chromium.org
Bug: 563816, 878545
Cq-Include-Trybots: luci.chromium.try:win_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_angle_rel_ng;luci.chromium.try:win_angle_rel_ng
Change-Id: I8c8b57fef830f85f26b231a6a22576d8f9159e0f
Reviewed-on: https://chromium-review.googlesource.com/1225605Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#592964}

DEPS

@@ -1103,7 +1103,7 @@ deps = {
     Var('chromium_git') + '/external/selenium/py.git' + '@' + '5fd78261a75fe08d27ca4835fb6c5ce4b42275bd',
 
   'src/third_party/webgl/src':
-    Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + '7ca87fb1d3da3b3d2060886e8c58e726d74c8219',
+    Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + '6d2f3f4cb8bac1f7c4a945c73d07a33df74f22f9',
 
   'src/third_party/webrtc':
     Var('webrtc_git') + '/src.git' + '@' + '0ad0c27a0bcee24ec9dc5c27df090034e152bd65',

content/test/gpu/gpu_tests/webgl_conformance_revision.txt

 # AUTOGENERATED FILE - DO NOT EDIT
 # SEE roll_webgl_conformance.py
-Current webgl revision 7ca87fb1d3da3b3d2060886e8c58e726d74c8219
+Current webgl revision 6d2f3f4cb8bac1f7c4a945c73d07a33df74f22f9