cc: Replace recorded region with direct map lookup

cc/layers/picture_layer_impl.cc

Index: cc/layers/picture_layer_impl.cc
diff --git a/cc/layers/picture_layer_impl.cc b/cc/layers/picture_layer_impl.cc
index e9c2c8e31b10c054201edb6cdb62b220d44d5773..3c2ab06842aa02a4f442d8cb2ea0ec45f173b9ad 100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -855,8 +855,7 @@ PictureLayerTiling* PictureLayerImpl::AddTiling(float contents_scale) {
 
   PictureLayerTiling* tiling = tilings_->AddTiling(contents_scale);
 
-  const Region& recorded = pile_->recorded_region();
-  DCHECK(!recorded.IsEmpty());
+  DCHECK(pile_->HasAnyRecordings());
 
   if (twin_layer_ && twin_layer_->should_use_gpu_rasterization() ==
       should_use_gpu_rasterization())
@@ -1167,7 +1166,7 @@ void PictureLayerImpl::ResetRasterScale() {
 bool PictureLayerImpl::CanHaveTilings() const {
   if (!DrawsContent())
     return false;
-  if (pile_->recorded_region().IsEmpty())
+  if (!pile_->HasAnyRecordings())
     return false;
   return true;
 }
@@ -1212,11 +1211,6 @@ void PictureLayerImpl::AsValueInto(base::DictionaryValue* state) const {
   state->Set("pictures", pile_->AsValue().release());
   state->Set("invalidation", invalidation_.AsValue().release());
 
-  Region unrecorded_region(gfx::Rect(pile_->size()));
-  unrecorded_region.Subtract(pile_->recorded_region());
-  if (!unrecorded_region.IsEmpty())
-    state->Set("unrecorded_region", unrecorded_region.AsValue().release());
-
   scoped_ptr<base::ListValue> coverage_tiles(new base::ListValue);
   for (PictureLayerTilingSet::CoverageIterator iter(tilings_.get(),
                                                     contents_scale_x(),