Implement a simple image cache for Sky in Dart (no eviction)

sky/engine/core/loader/CanvasImageLoader.cpp

Index: sky/engine/core/loader/CanvasImageLoader.cpp
diff --git a/sky/engine/core/loader/CanvasImageLoader.cpp b/sky/engine/core/loader/CanvasImageLoader.cpp
index 2879130d55f05359bc999197d30b0da43764e5d4..fd325826a9266204ee5a4e3740112fd31ff5c376 100644
--- a/sky/engine/core/loader/CanvasImageLoader.cpp
+++ b/sky/engine/core/loader/CanvasImageLoader.cpp
@@ -13,16 +13,13 @@ namespace blink {
 CanvasImageLoader::CanvasImageLoader(const String& src, PassOwnPtr<ImageLoaderCallback> callback)
   : callback_(callback) {
   // TODO(jackson): Figure out how to determine the proper base URL here
-  url_ = KURL(KURL(), src);
+  KURL url = KURL(KURL(), src);
+  fetcher_ = adoptPtr(new MojoFetcher(this, url));
 }
 
 CanvasImageLoader::~CanvasImageLoader() {
 }
 
-void CanvasImageLoader::load() {
-  fetcher_ = adoptPtr(new MojoFetcher(this, url_));
-}
-
 void CanvasImageLoader::OnReceivedResponse(mojo::URLResponsePtr response) {
   if (response->status_code != 200) {
     callback_->handleEvent(nullptr);