Fix crash in CompressedTexSubImage taking 0 offset without pbo

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 1a0d59bee3b5304da7029d7fb98f2773423ee167..90cf07d69babe23efe8dca7ff218a9636b5ec638 100644
--- a/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py
+++ b/content/test/gpu/gpu_tests/webgl2_conformance_expectations.py
@@ -41,10 +41,6 @@ class WebGL2ConformanceExpectations(WebGLConformanceExpectations):
     self.Skip('deqp/functional/gles3/builtinprecision/*.html', bug=619403)
 
     # All platforms.
-
-    self.Fail('conformance/extensions/webgl-compressed-texture-etc.html',
-        bug=679678)
-
     self.Flaky('conformance2/query/occlusion-query.html', bug=603168)
     self.Fail('conformance2/glsl3/tricky-loop-conditions.html', bug=483282)