cc: Remove all impl-side caps from RendererCapabilitiesImpl.

cc/test/pixel_test.cc

Index: cc/test/pixel_test.cc
diff --git a/cc/test/pixel_test.cc b/cc/test/pixel_test.cc
index 1399d88ad8e6c667ce98d859dbd4cd3b58a9545e..98ad27788d65f6c8f787195b0d32278cc94b6212 100644
--- a/cc/test/pixel_test.cc
+++ b/cc/test/pixel_test.cc
@@ -150,6 +150,7 @@ void PixelTest::SetUpGLRenderer(bool use_skia_gpu_backend,
   renderer_ = base::MakeUnique<GLRenderer>(
       &settings_.renderer_settings, output_surface_.get(),
       resource_provider_.get(), texture_mailbox_deleter_.get(), 0);
+  renderer_->Initialize();
   renderer_->SetVisible(true);
 }
 
@@ -193,6 +194,7 @@ void PixelTest::SetUpSoftwareRenderer() {
       resource_provider_.get());
   software_renderer_ = renderer.get();
   renderer_ = std::move(renderer);
+  renderer_->Initialize();
   renderer_->SetVisible(true);
 }