cc: Remove the base RasterSource

cc/test/fake_display_list_recording_source.cc

Index: cc/test/fake_display_list_recording_source.cc
diff --git a/cc/test/fake_display_list_recording_source.cc b/cc/test/fake_display_list_recording_source.cc
index 6bfb7f2c9d40ea7f69eaffca92d85403a4da6e90..9f792c74ed4236bd80ff1212068f9ade40076e68 100644
--- a/cc/test/fake_display_list_recording_source.cc
+++ b/cc/test/fake_display_list_recording_source.cc
@@ -14,8 +14,8 @@ bool FakeDisplayListRecordingSource::IsSuitableForGpuRasterization() const {
   return DisplayListRecordingSource::IsSuitableForGpuRasterization();
 }
 
-scoped_refptr<RasterSource> FakeDisplayListRecordingSource::CreateRasterSource(
-    bool can_use_lcd) const {
+scoped_refptr<DisplayListRasterSource>
+FakeDisplayListRecordingSource::CreateRasterSource(bool can_use_lcd) const {
   return FakeDisplayListRasterSource::CreateFromRecordingSourceWithWaitable(
       this, can_use_lcd, playback_allowed_event_);
 }