Post a microtask to load <img> elements.

Source/core/loader/ImageLoader.h

Index: Source/core/loader/ImageLoader.h
diff --git a/Source/core/loader/ImageLoader.h b/Source/core/loader/ImageLoader.h
index 589d2a8ed8f7ce9febc57df8fe96adc20684c60f..c905c187d2a4b89ae5d733a076817cadafc9aa09 100644
--- a/Source/core/loader/ImageLoader.h
+++ b/Source/core/loader/ImageLoader.h
@@ -59,7 +59,7 @@ public:
 
     // This function should be called when the element is attached to a document; starts
     // loading if a load hasn't already been started.
-    void updateFromElement();
+    void updateFromElement(bool calledFromTask = false, bool bypassMainWorldCSP = false);
 
     // This function should be called whenever the 'src' attribute is set, even if its value
     // doesn't change; starts new load unconditionally (matches Firefox and Opera behavior).
@@ -68,14 +68,14 @@ public:
     void elementDidMoveToNewDocument();
 
     Element* element() const { return m_element; }
-    bool imageComplete() const { return m_imageComplete; }
+    bool imageComplete() const { return m_imageComplete && !m_pendingTask; }
 
     ImageResource* image() const { return m_image.get(); }
     void setImage(ImageResource*); // Cancels pending load events, and doesn't dispatch new ones.
 
     void setLoadManually(bool loadManually) { m_loadManually = loadManually; }
 
-    bool hasPendingActivity() const { return m_hasPendingLoadEvent || m_hasPendingErrorEvent; }
+    bool hasPendingActivity() const { return m_hasPendingLoadEvent || m_hasPendingErrorEvent || m_pendingTask; }
 
     void dispatchPendingEvent(ImageEventSender*);
 
@@ -89,6 +89,8 @@ protected:
     virtual void notifyFinished(Resource*) OVERRIDE;
 
 private:
+    class Task;
+
     virtual void dispatchLoadEvent() = 0;
     virtual String sourceURI(const AtomicString&) const = 0;
 
@@ -106,6 +108,10 @@ private:
 
     void timerFired(Timer<ImageLoader>*);
 
+    // Used to determine whether to immediately initiate the load
+    // or to schedule a microtask.
+    bool shouldLoadImmediately(const KURL&) const;
+
     typedef WillBePersistentHeapHashSet<RawPtrWillBeWeakMember<ImageLoaderClient> > ImageLoaderClientSet;
 
     Element* m_element;
@@ -113,6 +119,7 @@ private:
     ImageLoaderClientSet m_clients;
     Timer<ImageLoader> m_derefElementTimer;
     AtomicString m_failedLoadURL;
+    Task* m_pendingTask; // owned by Microtask
     bool m_hasPendingLoadEvent : 1;
     bool m_hasPendingErrorEvent : 1;
     bool m_imageComplete : 1;