Roll Khronos WebGL conformance tests

BUG=415609,415688
TEST=gpu bots
TBR=kbr@chromium.org

Review URL: https://codereview.chromium.org/580183002

Cr-Commit-Position: refs/heads/master@{#295553}

DEPS

@@ -191,7 +191,7 @@ deps = {
     Var('chromium_git') + '/external/bidichecker/lib.git' + '@' + '97f2aa645b74c28c57eca56992235c79850fa9e0',
 
   'src/third_party/webgl/src':
-   Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + '5906d1bcdd525d7d00914f1d4e43f7075452c43c',
+   Var('chromium_git') + '/external/khronosgroup/webgl.git' + '@' + 'b1a7210dc4034793e34a2149cb571e85700a85f2',
 
   'src/third_party/swig/Lib':
    Var('chromium_git') + '/chromium/deps/swig/Lib.git' + '@' + 'f2a695d52e61e6a8d967731434f165ed400f0d69',

content/test/gpu/gpu_tests/webgl_conformance_expectations.py

@@ -37,6 +37,8 @@ class WebGLConformanceExpectations(test_expectations.TestExpectations):
         ['win'], bug=391957)
     self.Fail('conformance/glsl/bugs/conditional-discard-in-loop.html',
         ['win'], bug=402195)
+    self.Fail('conformance/attribs/gl-bindAttribLocation-matrix.html',
+        ['win'], bug=415688)
 
     # Win7 / Intel failures
     self.Fail('conformance/rendering/gl-scissor-test.html',