cc: Inflate invalidation in each picture list

cc/resources/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/resources/picture_layer_tiling.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/debug/trace_event.h"
@@ skipping 24 matching lines @@
     : contents_scale_(contents_scale),
       layer_bounds_(layer_bounds),
       resolution_(NON_IDEAL_RESOLUTION),
       client_(client),
       tiling_data_(gfx::Size(), gfx::Size(), true),
       last_impl_frame_time_in_seconds_(0.0) {
   gfx::Size content_bounds =
       gfx::ToCeiledSize(gfx::ScaleSize(layer_bounds, contents_scale));
   gfx::Size tile_size = client_->CalculateTileSize(content_bounds);
 
+  DCHECK(!gfx::ToFlooredSize(
+      gfx::ScaleSize(layer_bounds, contents_scale)).IsEmpty()) <<
+      "Tiling created with scale too small as contents become empty. " <<
+      "Layer bounds: " << layer_bounds.ToString() <<
+      "Contents scale: " << contents_scale;
+
   tiling_data_.SetTotalSize(content_bounds);
   tiling_data_.SetMaxTextureSize(tile_size);
 }
 
 PictureLayerTiling::~PictureLayerTiling() {
 }
 
 void PictureLayerTiling::SetClient(PictureLayerTilingClient* client) {
   client_ = client;
 }
@@ skipping 545 matching lines @@
 
     // If our delta is less then our event distance, we're done.
     if (delta < event.distance)
       break;
   }
 
   return gfx::Rect(origin_x, origin_y, width, height);
 }
 
 }  // namespace cc