cc: Recreate small layer tiles when size changes

cc/picture_layer_tiling.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/picture_layer_tiling.h"
 
 #include "base/debug/trace_event.h"
 #include "cc/math_util.h"
 #include "ui/gfx/point_conversions.h"
 #include "ui/gfx/rect_conversions.h"
@@ skipping 74 matching lines @@
     tiles_.clear();
     return;
   }
 
   gfx::Size tile_size = client_->CalculateTileSize(
       tiling_data_.max_texture_size(),
       content_bounds);
   if (tile_size != tiling_data_.max_texture_size()) {
     tiling_data_.SetMaxTextureSize(tile_size);
     tiles_.clear();
+    CreateTilesFromLayerRect(gfx::Rect(layer_bounds_));

[danakj, 2013/02/12 01:31:20]

What if you set old_layer_bounds to empty here? Would that allow better reuse of
the code below instead of early out?

[enne (OOO), 2013/02/12 01:34:39]

Hmm.  I'm not sure the single line of reuse makes it worth the extra
complication.

[danakj, 2013/02/12 01:36:24]

For instance, if you did it that way, you'd also get an Invalidate over the
whole layer. Why do you want to skip that here?

[danakj, 2013/02/12 01:37:56]

(Especially considering Justin's desire to record somehow based on the tile
size).

+    return;
   }
 
   // Any tiles outside our new bounds are invalid and should be dropped.
   if (old_content_bounds.width() > content_bounds.width() ||
       old_content_bounds.height() > content_bounds.height()) {
     int right =
         tiling_data_.TileXIndexFromSrcCoord(content_bounds.width() - 1);
     int bottom =
         tiling_data_.TileYIndexFromSrcCoord(content_bounds.height() - 1);
 
@@ skipping 393 matching lines @@
     // and recreated, then that picture pile ref could exist indefinitely.  To
     // prevent this, ask the client to update the pile to its own ref.  This
     // will cause PicturePileImpls and their clones to get deleted once the
     // corresponding PictureLayerImpl and any in flight raster jobs go out of
     // scope.
     client_->UpdatePile(it->second);
   }
 }
 
 }  // namespace cc