[blimp] Add SkPicture caching support.

cc/layers/picture_layer.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layers/picture_layer.h"
 
 #include "base/auto_reset.h"
 #include "base/trace_event/trace_event.h"
 #include "cc/layers/content_layer_client.h"
 #include "cc/layers/picture_layer_impl.h"
@@ skipping 161 matching lines @@
 void PictureLayer::SetTypeForProtoSerialization(proto::LayerNode* proto) const {
   proto->set_type(proto::LayerNode::PICTURE_LAYER);
 }
 
 void PictureLayer::LayerSpecificPropertiesToProto(
     proto::LayerProperties* proto) {
   Layer::LayerSpecificPropertiesToProto(proto);
   DropRecordingSourceContentIfInvalid();
 
   proto::PictureLayerProperties* picture = proto->mutable_picture();
-  recording_source_->ToProtobuf(
-      picture->mutable_recording_source(),
-      layer_tree_host()->image_serialization_processor());
+  recording_source_->ToProtobuf(picture->mutable_recording_source());
+
+  // Add all SkPicture items to the picture cache.
+  scoped_refptr<const DisplayItemList> display_list =

[vmpstr, 2016/06/24 18:58:32]

i think you can 

const scoped_refptr<const DisplayItemList>& 

here... or maybe GetDisplayItemList can return a raw ptr?

[nyquist, 2016/06/24 20:31:23]

Done.

+      recording_source_->GetDisplayItemList();
+  if (display_list) {
+    for (auto it = display_list->begin(); it != display_list->end(); ++it) {
+      sk_sp<const SkPicture> picture = it->GetPicture();
+      // Only DrawingDisplayItems have SkPictures.
+      if (!picture)
+        continue;
+
+      layer_tree_host()->engine_picture_cache()->MarkUsed(picture.get());
+    }
+  }
+
   RegionToProto(last_updated_invalidation_, picture->mutable_invalidation());
   picture->set_is_mask(is_mask_);
   picture->set_nearest_neighbor(nearest_neighbor_);
 
   picture->set_update_source_frame_number(update_source_frame_number_);
 
   last_updated_invalidation_.Clear();
 }
 
 void PictureLayer::FromLayerSpecificPropertiesProto(
     const proto::LayerProperties& proto) {
   Layer::FromLayerSpecificPropertiesProto(proto);
   const proto::PictureLayerProperties& picture = proto.picture();
   // If this is a new layer, ensure it has a recording source. During layer
   // hierarchy deserialization, ::SetLayerTreeHost(...) is not called, but
   // instead the member is set directly, so it needs to be set here explicitly.
   if (!recording_source_)
     recording_source_.reset(new RecordingSource);
 
-  recording_source_->FromProtobuf(
-      picture.recording_source(),
-      layer_tree_host()->image_serialization_processor());
+  std::vector<uint32_t> used_engine_picture_ids;
+  recording_source_->FromProtobuf(picture.recording_source(),
+                                  layer_tree_host()->client_picture_cache(),
+                                  &used_engine_picture_ids);
+
+  // Inform picture cache about which SkPictures are now in use.
+  for (uint32_t engine_picture_id : used_engine_picture_ids)
+    layer_tree_host()->client_picture_cache()->MarkUsed(engine_picture_id);
 
   Region new_invalidation = RegionFromProto(picture.invalidation());
   last_updated_invalidation_.Swap(&new_invalidation);
   is_mask_ = picture.is_mask();
   nearest_neighbor_ = picture.nearest_neighbor();
 
   update_source_frame_number_ = picture.update_source_frame_number();
 }
 
 void PictureLayer::RunMicroBenchmark(MicroBenchmark* benchmark) {
@@ skipping 18 matching lines @@
   if (update_source_frame_number_ != source_frame_number &&
       recording_source_bounds != layer_bounds) {
     // Update may not get called for the layer (if it's not in the viewport
     // for example), even though it has resized making the recording source no
     // longer valid. In this case just destroy the recording source.
     recording_source_->SetEmptyBounds();
   }
 }
 
 }  // namespace cc