Serialize DisplayListRecordingSource to protos.

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 c48859efd455c5756c5664e3cf7d4ac19408cee4..fe0a1270e9c21a1622a41a898f36510857f514bf 100644
--- a/cc/test/fake_display_list_recording_source.cc
+++ b/cc/test/fake_display_list_recording_source.cc
@@ -5,6 +5,7 @@
 #include "cc/test/fake_display_list_recording_source.h"
 
 #include "cc/test/fake_display_list_raster_source.h"
+#include "cc/test/skia_common.h"
 
 namespace cc {
 
@@ -24,4 +25,22 @@ FakeDisplayListRecordingSource::CreateRasterSource(bool can_use_lcd) const {
       this, can_use_lcd, playback_allowed_event_);
 }
 
+bool FakeDisplayListRecordingSource::EqualsTo(
+    const FakeDisplayListRecordingSource& other) {
+  return recorded_viewport_ == other.recorded_viewport_ &&
+         size_ == other.size_ &&
+         slow_down_raster_scale_factor_for_debug_ ==
+             other.slow_down_raster_scale_factor_for_debug_ &&
+         generate_discardable_images_metadata_ ==
+             other.generate_discardable_images_metadata_ &&
+         requires_clear_ == other.requires_clear_ &&
+         is_solid_color_ == other.is_solid_color_ &&
+         clear_canvas_with_debug_color_ ==
+             other.clear_canvas_with_debug_color_ &&
+         solid_color_ == other.solid_color_ &&
+         background_color_ == other.background_color_ &&
+         AreDisplayListDrawingResultsSame(recorded_viewport_, display_list_,
+                                          other.display_list_);
+}
+
 }  // namespace cc