WebGL: Re-add dynamic indexing test suppression.

content/test/gpu/gpu_tests/webgl2_conformance_expectations.py

Index: content/test/gpu/gpu_tests/webgl2_conformance_expectations.py
diff --git a/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py b/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py
index 4da7bece826ceed4719187bebf2dd40b4bb800f5..bb04ecc14419785b498b6c2c42863b22511ca0b7 100644
--- a/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py
+++ b/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py
@@ -55,6 +55,10 @@ class WebGL2ConformanceExpectations(WebGLConformanceExpectations):
     self.Fail('deqp/functional/gles3/fboinvalidate/sub.html',
         ['win'], bug=1246) # ANGLE bug.
 
+    # TODO(jmadill): Remove once we re-land the ANGLE CL.
+    self.Fail('conformance2/glsl3/vector-dynamic-indexing.html',
+        ['win'], bug=638313)
+
     # Windows 8 only.
     self.Flaky('deqp/functional/gles3/buffercopy.html', ['win8'], bug=587601)