cc: Explicitly invalidate all dropped recordings on the main thread.

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 <limits>
 
 #include "base/time/time.h"
@@ skipping 90 matching lines @@
   // disappears.
   layer_impl->twin_layer_ = NULL;
   twin_layer_ = NULL;
 
   layer_impl->SetIsMask(is_mask_);
   layer_impl->pile_ = pile_;
 
   // Tilings would be expensive to push, so we swap.
   layer_impl->tilings_.swap(tilings_);
 
-  // Ensure that we don't have any tiles that are out of date.
-  if (tilings_)
-    tilings_->RemoveTilesInRegion(invalidation_);
-
   layer_impl->tilings_->SetClient(layer_impl);
   if (tilings_)
     tilings_->SetClient(this);
 
   layer_impl->raster_page_scale_ = raster_page_scale_;
   layer_impl->raster_device_scale_ = raster_device_scale_;
   layer_impl->raster_source_scale_ = raster_source_scale_;
   layer_impl->raster_contents_scale_ = raster_contents_scale_;
   layer_impl->low_res_raster_contents_scale_ = low_res_raster_contents_scale_;
   layer_impl->needs_post_commit_initialization_ = false;
@@ skipping 540 matching lines @@
     RemoveAllTilings();
     return;
   }
 
   raster_page_scale_ = other->raster_page_scale_;
   raster_device_scale_ = other->raster_device_scale_;
   raster_source_scale_ = other->raster_source_scale_;
   raster_contents_scale_ = other->raster_contents_scale_;
   low_res_raster_contents_scale_ = other->low_res_raster_contents_scale_;
 
-  // Union in the other newly exposed regions as invalid.
-  Region difference_region = Region(gfx::Rect(bounds()));
-  difference_region.Subtract(gfx::Rect(other->bounds()));
-  invalidation_.Union(difference_region);
+  // The tilings on this layer were swapped here from the active layer on
+  // activation, so they have not seen the invalidation that was given to
+  // the active layer. So union that invalidation in here, but don't save
+  // it and pass it back to the active layer again.
+  Region invalidation_from_pending_and_active =
+      UnionRegions(invalidation_, other->invalidation_);
 
   bool synced_high_res_tiling = false;
   if (CanHaveTilings()) {
-    synced_high_res_tiling = tilings_->SyncTilings(
-        *other->tilings_, bounds(), invalidation_, MinimumContentsScale());
+    synced_high_res_tiling =
+        tilings_->SyncTilings(*other->tilings_,
+                              bounds(),
+                              invalidation_from_pending_and_active,
+                              MinimumContentsScale());
   } else {
     RemoveAllTilings();
   }
 
   // If our MinimumContentsScale has changed to prevent the twin's high res
   // tiling from being synced, we should reset the raster scale and let it be
   // recalculated (1) again. This can happen if our bounds shrink to the point
   // where min contents scale grows.
   // (1) - TODO(vmpstr) Instead of hoping that this will be recalculated, we
   // should refactor this code a little bit and actually recalculate this.
@@ skipping 935 matching lines @@
   return iterator_index_ < iterators_.size();
 }
 
 bool PictureLayerImpl::LayerEvictionTileIterator::IsCorrectType(
     PictureLayerTiling::TilingEvictionTileIterator* it) const {
   return it->get_type() == iteration_stage_ &&
          (**it)->required_for_activation() == required_for_activation_;
 }
 
 }  // namespace cc