Disable ETC1 textures on WebGL 1 on ANGLE

BUG=658929
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2576813002
Cr-Commit-Position: refs/heads/master@{#438638}

content/test/gpu/gpu_tests/webgl_conformance_expectations.py

@@ -51,7 +51,7 @@ class WebGLConformanceExpectations(GpuTestExpectations):
     self.Skip('WebglExtension_WEBGL_compressed_texture_atc',
         ['win', 'mac', 'linux'])
     self.Skip('WebglExtension_WEBGL_compressed_texture_etc1',
-        ['mac', 'linux'])
+        ['win', 'mac', 'linux'])
     self.Skip('WebglExtension_WEBGL_compressed_texture_pvrtc',
         ['win', 'mac', 'linux'])
     self.Skip('WebglExtension_WEBGL_compressed_texture_s3tc_srgb',
@@ -62,8 +62,6 @@ class WebGLConformanceExpectations(GpuTestExpectations):
         ['win', 'd3d9'])
     self.Fail('WebglExtension_EXT_sRGB',
         ['win', 'd3d9'])
-    self.Fail('WebglExtension_WEBGL_compressed_texture_etc1',
-        ['win', 'd3d9'])
 
     self.Fail('WebglExtension_WEBGL_depth_texture',
         ['win', 'amd', 'd3d9'])

gpu/command_buffer/service/feature_info.cc

@@ -1037,7 +1037,11 @@ void FeatureInfo::InitializeFeatures() {
     validators_.g_l_state.AddValue(GL_TEXTURE_BINDING_EXTERNAL_OES);
   }
 
-  if (extensions.Contains("GL_OES_compressed_ETC1_RGB8_texture")) {
+  // TODO(kainino): If we add a way to query whether ANGLE is exposing
+  // native support for ETC1 textures, require that here. Otherwise, we could
+  // co-opt the native-ETC2-support query discussed below.
+  if (extensions.Contains("GL_OES_compressed_ETC1_RGB8_texture") &&
+      !gl_version_info_->is_angle) {
     AddExtensionString("GL_OES_compressed_ETC1_RGB8_texture");
     feature_flags_.oes_compressed_etc1_rgb8_texture = true;
     validators_.compressed_texture_format.AddValue(GL_ETC1_RGB8_OES);

third_party/WebKit/Source/modules/webgl/WebGLCompressedTextureETC1.cpp

@@ -25,12 +25,8 @@ WebGLCompressedTextureETC1* WebGLCompressedTextureETC1::create(
 
 bool WebGLCompressedTextureETC1::supported(WebGLRenderingContextBase* context) {
   Extensions3DUtil* extensionsUtil = context->extensionsUtil();
-  bool webgl1 = !context->isWebGL2OrHigher();
-  bool etc1 =
-      extensionsUtil->supportsExtension("GL_OES_compressed_ETC1_RGB8_texture");
-  bool etc =
-      extensionsUtil->supportsExtension("GL_CHROMIUM_compressed_texture_etc");
-  return (webgl1 || etc) && etc1;
+  return extensionsUtil->supportsExtension(
+      "GL_OES_compressed_ETC1_RGB8_texture");
 }
 
 const char* WebGLCompressedTextureETC1::extensionName() {