Revert of cc: Remove tile sharing from tilings.

cc/resources/picture_layer_tiling_set.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/resources/picture_layer_tiling_set.h"
 
 #include <limits>
 #include <set>
 #include <vector>
 
@@ skipping 37 matching lines @@
       skewport_extrapolation_limit_in_content_pixels_(
           skewport_extrapolation_limit_in_content_pixels),
       client_(client) {
 }
 
 PictureLayerTilingSet::~PictureLayerTilingSet() {
 }
 
 void PictureLayerTilingSet::CopyTilingsAndPropertiesFromPendingTwin(
     const PictureLayerTilingSet* pending_twin_set,
-    const scoped_refptr<RasterSource>& raster_source,
-    const Region& layer_invalidation) {
+    const scoped_refptr<RasterSource>& raster_source) {
   if (pending_twin_set->tilings_.empty()) {
     // If the twin (pending) tiling set is empty, it was not updated for the
     // current frame. So we drop tilings from our set as well, instead of
     // leaving behind unshared tilings that are all non-ideal.
     RemoveAllTilings();
     return;
   }
 
   bool tiling_sort_required = false;
   for (PictureLayerTiling* pending_twin_tiling : pending_twin_set->tilings_) {
     float contents_scale = pending_twin_tiling->contents_scale();
     PictureLayerTiling* this_tiling = FindTilingWithScale(contents_scale);
     if (!this_tiling) {
       scoped_ptr<PictureLayerTiling> new_tiling = PictureLayerTiling::Create(
           contents_scale, raster_source, client_, max_tiles_for_interest_area_,
           skewport_target_time_in_seconds_,
           skewport_extrapolation_limit_in_content_pixels_);
       tilings_.push_back(new_tiling.Pass());
       this_tiling = tilings_.back();
       tiling_sort_required = true;
     }
-    this_tiling->TakeTilesAndPropertiesFrom(pending_twin_tiling,
-                                            layer_invalidation);
+    this_tiling->CloneTilesAndPropertiesFrom(*pending_twin_tiling);
   }
 
   if (tiling_sort_required)
     tilings_.sort(LargestToSmallestScaleFunctor());
 }
 
 void PictureLayerTilingSet::UpdateTilingsToCurrentRasterSourceForActivation(
     scoped_refptr<RasterSource> raster_source,
     const PictureLayerTilingSet* pending_twin_set,
     const Region& layer_invalidation,
     float minimum_contents_scale,
     float maximum_contents_scale) {
   RemoveTilingsBelowScale(minimum_contents_scale);
   RemoveTilingsAboveScale(maximum_contents_scale);
 
   // Copy over tilings that are shared with the |pending_twin_set| tiling set.
   // Also, copy all of the properties from twin tilings.
-  CopyTilingsAndPropertiesFromPendingTwin(pending_twin_set, raster_source,
-                                          layer_invalidation);
+  CopyTilingsAndPropertiesFromPendingTwin(pending_twin_set, raster_source);
 
   // If the tiling is not shared (FindTilingWithScale returns nullptr), then
   // invalidate tiles and update them to the new raster source.
   for (PictureLayerTiling* tiling : tilings_) {
     if (pending_twin_set->FindTilingWithScale(tiling->contents_scale()))
       continue;
 
     tiling->SetRasterSourceAndResize(raster_source);
     tiling->Invalidate(layer_invalidation);
     tiling->SetRasterSourceOnTiles();
@@ skipping 30 matching lines @@
   }
   VerifyTilings(nullptr /* pending_twin_set */);
 }
 
 void PictureLayerTilingSet::UpdateRasterSourceDueToLCDChange(
     const scoped_refptr<RasterSource>& raster_source,
     const Region& layer_invalidation) {
   for (PictureLayerTiling* tiling : tilings_) {
     tiling->SetRasterSourceAndResize(raster_source);
     tiling->Invalidate(layer_invalidation);
-    // Since the invalidation changed, we need to create any missing tiles in
-    // the live tiles rect again.
-    tiling->CreateMissingTilesInLiveTilesRect();
     tiling->VerifyAllTilesHaveCurrentRasterSource();
   }
 }
 
 void PictureLayerTilingSet::VerifyTilings(
     const PictureLayerTilingSet* pending_twin_set) const {
 #if DCHECK_IS_ON()
   for (PictureLayerTiling* tiling : tilings_) {
     DCHECK(tiling->tile_size() ==
            client_->CalculateTileSize(tiling->tiling_size()))
@@ skipping 425 matching lines @@
     case LOWER_THAN_LOW_RES:
       range = TilingRange(low_res_range.end, tilings_.size());
       break;
   }
 
   DCHECK_LE(range.start, range.end);
   return range;
 }
 
 }  // namespace cc