Clear Image Decode Cache on Navigation

cc/tiles/image_controller_unittest.cc

Index: cc/tiles/image_controller_unittest.cc
diff --git a/cc/tiles/image_controller_unittest.cc b/cc/tiles/image_controller_unittest.cc
index ce728c36d2cbb797fbc02cb1caf4cffeb2929227..6e6dc247d87817c086a8d4d65c805d376f351472 100644
--- a/cc/tiles/image_controller_unittest.cc
+++ b/cc/tiles/image_controller_unittest.cc
@@ -128,6 +128,7 @@ class TestableCache : public ImageDecodeCache {
   void ReduceCacheUsage() override {}
   void SetShouldAggressivelyFreeResources(
       bool aggressively_free_resources) override {}
+  void ClearCache() override {}
 
   int number_of_refs() const { return number_of_refs_; }
   void SetTaskToUse(scoped_refptr<TileTask> task) { task_to_use_ = task; }