cc: Fix tiling raster tile iterator to handle initializing tiles.

This patch ensures that if a tile is initialized mid-iteration (as is
desirable in some unittests), then it will continue working as expected.

R=reveman

Review URL: https://codereview.chromium.org/295933008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@273025 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 7 insertions, 5 deletions

diff --git a/cc/resources/picture_layer_tiling.cc b/cc/resources/picture_layer_tiling.cc
index f0b38db..9ab2cf5 100644
--- a/cc/resources/picture_layer_tiling.cc
+++ b/cc/resources/picture_layer_tiling.cc
@@ -859,8 +859,10 @@ void PictureLayerTiling::TilingRasterTileIterator::AdvancePhase() {
       ++spiral_iterator_;
     }
 
-    if (!spiral_iterator_ && type_ == TilePriority::EVENTUALLY)
+    if (!spiral_iterator_ && type_ == TilePriority::EVENTUALLY) {
+      current_tile_ = NULL;
       break;
+    }
   } while (!spiral_iterator_);
 }
 
@@ -901,8 +903,10 @@ operator++() {
         break;
       case TilePriority::EVENTUALLY:
         ++spiral_iterator_;
-        if (!spiral_iterator_)
+        if (!spiral_iterator_) {
+          current_tile_ = NULL;
           return *this;
+        }
         next_index = spiral_iterator_.index();
         break;
     }
diff --git a/cc/resources/picture_layer_tiling.h b/cc/resources/picture_layer_tiling.h
index feb40ff..131e338 100644
--- a/cc/resources/picture_layer_tiling.h
+++ b/cc/resources/picture_layer_tiling.h
@@ -51,9 +51,7 @@ class CC_EXPORT PictureLayerTiling {
     TilingRasterTileIterator(PictureLayerTiling* tiling, WhichTree tree);
     ~TilingRasterTileIterator();
 
-    operator bool() const {
-      return current_tile_ && TileNeedsRaster(current_tile_);
-    }
+    operator bool() const { return !!current_tile_; }
     Tile* operator*() { return current_tile_; }
     TilePriority::PriorityBin get_type() const { return type_; }