cc: Add image decode control in the compositor.

cc/layers/picture_layer_impl.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_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <set>
@@ skipping 520 matching lines @@
   DCHECK(raster_source->GetSize().IsEmpty() ||
          bounds() == raster_source->GetSize())
       << " bounds " << bounds().ToString() << " pile "
       << raster_source->GetSize().ToString();
 
   // The |raster_source_| is initially null, so have to check for that for the
   // first frame.
   bool could_have_tilings = raster_source_.get() && CanHaveTilings();
   raster_source_.swap(raster_source);
 
+  // Only set the image decode controller when we're committing.

[enne (OOO), 2015/12/02 23:33:25]

...for efficiency's sake? It'd still be set later, right?

Maybe PictureLayer::PushPropertiesTo should just do this always after creating
the raster source during commit, rather than conditionally doing it here?

[vmpstr, 2015/12/03 21:20:23]

This effectively does just this. PictureLayer sets the raster source via this
function during PushPropertiesTo (with pending_set == nullptr)

I can do:

layer_impl->layer_tree_impl()->tile_manager()->GetImageDecodeController()

in PictureLayer::PushPropertiesTobut it just feels a bit yucky to reach into
layer_tree_impl from picture layer :P

Wdyt?

+  if (!pending_set) {
+    raster_source_->SetImageDecodeController(
+        layer_tree_impl()->tile_manager()->GetImageDecodeController());
+  }
+
   // The |new_invalidation| must be cleared before updating tilings since they
   // access the invalidation through the PictureLayerTilingClient interface.
   invalidation_.Clear();
   invalidation_.Swap(new_invalidation);
 
   bool can_have_tilings = CanHaveTilings();
   DCHECK(!pending_set ||
          can_have_tilings == GetPendingOrActiveTwinLayer()->CanHaveTilings());
 
   // Need to call UpdateTiles again if CanHaveTilings changed.
@@ skipping 689 matching lines @@
 
 bool PictureLayerImpl::IsOnActiveOrPendingTree() const {
   return !layer_tree_impl()->IsRecycleTree();
 }
 
 bool PictureLayerImpl::HasValidTilePriorities() const {
   return IsOnActiveOrPendingTree() && IsDrawnRenderSurfaceLayerListMember();
 }
 
 }  // namespace cc