cc: Add checker-imaging support to TileManager.

cc/layers/picture_layer_impl.cc

Index: cc/layers/picture_layer_impl.cc
diff --git a/cc/layers/picture_layer_impl.cc b/cc/layers/picture_layer_impl.cc
index ee0a6c8495917a0e78ad3159bf8b23aab94dbc57..193d5fc4b6c2e57a94702a9f7a702f01298b422c 100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -1367,4 +1367,24 @@ bool PictureLayerImpl::HasValidTilePriorities() const {
          is_drawn_render_surface_layer_list_member();
 }
 
+void PictureLayerImpl::InvalidateRegionForImages(
+    const std::unordered_set<ImageId>& images_to_invalidate) {
+  TRACE_EVENT_BEGIN0("cc", "PictureLayerImpl::InvalidateRegionForImages");
+
+  InvalidationRegion image_invalidation;
+  for (auto image_id : images_to_invalidate)
+    image_invalidation.Union(raster_source_->GetRectForImage(image_id));
+  Region invalidation;
+  image_invalidation.Swap(&invalidation);
+
+  TRACE_EVENT_END1("cc", "PictureLayerImpl::InvalidateRegionForImages",

[vmpstr, 2017/02/13 22:49:30]

Hmm, this doesn't capture the duration of the
Union/UpdateTilingsForImplSideInvalidation though. Can we move the end trace in
both the early out and at the end of the function?

[Khushal, 2017/02/14 05:10:22]

Done.

+                   "Invalidation", invalidation.ToString());
+
+  if (invalidation.IsEmpty())
+    return;
+  invalidation_.Union(invalidation);
+  tilings_->UpdateTilingsForImplSideInvalidation(invalidation);
+  SetNeedsPushProperties();
+}
+
 }  // namespace cc