Allow eviction of ImageBitmaps that are created from ImageElements.

Source/core/loader/ImageLoader.cpp

Index: Source/core/loader/ImageLoader.cpp
diff --git a/Source/core/loader/ImageLoader.cpp b/Source/core/loader/ImageLoader.cpp
index 9fbabee79622c331ba92247f7abdc00eb8968b9a..73fa90a5042561d00acf68b6469811382e4ad928 100644
--- a/Source/core/loader/ImageLoader.cpp
+++ b/Source/core/loader/ImageLoader.cpp
@@ -115,6 +115,7 @@ void ImageLoader::setImageWithoutConsideringPendingLoadEvent(CachedImage* newIma
     ASSERT(m_failedLoadURL.isEmpty());
     CachedImage* oldImage = m_image.get();
     if (newImage != oldImage) {
+        sourceImageChanged();
         m_image = newImage;
         if (m_hasPendingBeforeLoadEvent) {
             beforeLoadEventSender().cancelEvent(this);
@@ -190,9 +191,11 @@ void ImageLoader::updateFromElement()
         m_hasPendingErrorEvent = true;
         errorEventSender().dispatchEventSoon(this);
     }
-    
+
     CachedImage* oldImage = m_image.get();
     if (newImage != oldImage) {
+        sourceImageChanged();
+
         if (m_hasPendingBeforeLoadEvent) {
             beforeLoadEventSender().cancelEvent(this);
             m_hasPendingBeforeLoadEvent = false;
@@ -444,6 +447,15 @@ void ImageLoader::elementDidMoveToNewDocument()
     setImage(0);
 }
 
+void ImageLoader::sourceImageChanged()
+{
+    HashSet<ImageLoaderClient*>::iterator end = m_clients.end();
+    for (HashSet<ImageLoaderClient*>::iterator it = m_clients.begin(); it != end; ++it) {
+        ImageLoaderClient* handle = *it;
+        handle->notifyImageSourceChanged();
+    }
+}
+
 inline void ImageLoader::clearFailedLoadURL()
 {
     m_failedLoadURL = AtomicString();