Remove WebGraphicsContext3D getter from cc::ContextProvider

cc/output/output_surface_unittest.cc

Index: cc/output/output_surface_unittest.cc
diff --git a/cc/output/output_surface_unittest.cc b/cc/output/output_surface_unittest.cc
index 551ec595593b6336475574023a4f62ffd4ec02c2..9007a9a49eef4f9b5e076667a102a1b51d85d13b 100644
--- a/cc/output/output_surface_unittest.cc
+++ b/cc/output/output_surface_unittest.cc
@@ -142,8 +142,9 @@ TEST(OutputSurfaceTest, ClientPointerIndicatesBindToClientSuccess) {
 
   // Verify DidLoseOutputSurface callback is hooked up correctly.
   EXPECT_FALSE(client.did_lose_output_surface_called());
-  output_surface.context_provider()->Context3d()->loseContextCHROMIUM(
+  output_surface.context_provider()->ContextGL()->LoseContextCHROMIUM(
       GL_GUILTY_CONTEXT_RESET_ARB, GL_INNOCENT_CONTEXT_RESET_ARB);
+  output_surface.context_provider()->ContextGL()->Flush();
   EXPECT_TRUE(client.did_lose_output_surface_called());
 }
 
@@ -197,8 +198,9 @@ TEST_F(OutputSurfaceTestInitializeNewContext3d, Success) {
   EXPECT_EQ(context_provider_, output_surface_.context_provider());
 
   EXPECT_FALSE(client_.did_lose_output_surface_called());
-  context_provider_->Context3d()->loseContextCHROMIUM(
+  context_provider_->ContextGL()->LoseContextCHROMIUM(
       GL_GUILTY_CONTEXT_RESET_ARB, GL_INNOCENT_CONTEXT_RESET_ARB);
+  context_provider_->ContextGL()->Flush();
   EXPECT_TRUE(client_.did_lose_output_surface_called());
 
   output_surface_.ReleaseGL();