Re-land: cc: Add raster finished signals to RasterWorkerPool.

cc/resources/tile.h

Index: cc/resources/tile.h
diff --git a/cc/resources/tile.h b/cc/resources/tile.h
index 2cd49971ec55c12fafa637b0db33534d8bc5faec..d4d8c0e5d4b947c3c1309d85e6d03415184f9dd3 100644
--- a/cc/resources/tile.h
+++ b/cc/resources/tile.h
@@ -98,22 +98,10 @@ class CC_EXPORT Tile : public base::RefCounted<Tile> {
     picture_pile_ = pile;
   }
 
-  // For test only methods.
-  bool HasRasterTaskForTesting() const {
-    for (int mode = 0; mode < NUM_RASTER_MODES; ++mode) {
-      if (!managed_state().tile_versions[mode].raster_task_.is_null())
-        return true;
-    }
-    return false;
-  }
-  void ResetRasterTaskForTesting() {
-    for (int mode = 0; mode < NUM_RASTER_MODES; ++mode)
-      managed_state().tile_versions[mode].raster_task_.Reset();
-  }
-
  private:
   // Methods called by by tile manager.
   friend class TileManager;
+  friend class FakeTileManager;
   friend class BinComparator;
   ManagedTileState& managed_state() { return managed_state_; }
   const ManagedTileState& managed_state() const { return managed_state_; }