DO NOT COMMIT: Experimental removal of encoded image data

third_party/WebKit/Source/core/loader/ImageLoader.cpp

Index: third_party/WebKit/Source/core/loader/ImageLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/ImageLoader.cpp b/third_party/WebKit/Source/core/loader/ImageLoader.cpp
index 86f65618292a28c53500d98bb06686c25897ba40..2f74bcb9eaed7bc2eedd0e6346d5ed8a75a965d8 100644
--- a/third_party/WebKit/Source/core/loader/ImageLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/ImageLoader.cpp
@@ -154,6 +154,7 @@ ImageLoader::ImageLoader(Element* element)
     , m_loadingImageDocument(false)
     , m_elementIsProtected(false)
     , m_suppressErrorEvents(false)
+    , m_suppressEvents(false)
 {
     RESOURCE_LOADING_DVLOG(1) << "new ImageLoader " << this;
     ThreadState::current()->registerPreFinalizer(this);
@@ -232,6 +233,9 @@ static void configureRequest(FetchRequest& request, ImageLoader::BypassMainWorld
 
 inline void ImageLoader::dispatchErrorEvent()
 {
+    if (m_suppressEvents) {
+        return;
+    }
     m_hasPendingErrorEvent = true;
     errorEventSender().dispatchEventSoon(this);
 }
@@ -279,9 +283,17 @@ void ImageLoader::doUpdateFromElement(BypassMainWorldBehavior bypassBehavior, Up
         // Unlike raw <img>, we block mixed content inside of <picture> or <img srcset>.
         ResourceLoaderOptions resourceLoaderOptions = ResourceFetcher::defaultResourceOptions();
         ResourceRequest resourceRequest(url);
-        if (updateBehavior == UpdateForcedReload) {
+        switch (updateBehavior) {
+        case UpdateForcedReload:
             resourceRequest.setCachePolicy(WebCachePolicy::BypassingCache);
             resourceRequest.setLoFiState(WebURLRequest::LoFiOff);
+            break;
+        case UpdateMyReload:
+            resourceRequest.setCachePolicy(WebCachePolicy::ReturnCacheDataElseLoad);
+            resourceRequest.setLoFiState(WebURLRequest::LoFiOff);
+            break;
+        default:
+            break;
         }
 
         if (referrerPolicy != ReferrerPolicyDefault)
@@ -327,7 +339,7 @@ void ImageLoader::doUpdateFromElement(BypassMainWorldBehavior bypassBehavior, Up
         }
 
         m_image = newImage;
-        m_hasPendingLoadEvent = newImage;
+        m_hasPendingLoadEvent = newImage && !m_suppressEvents;
         m_imageComplete = !newImage;
 
         updateLayoutObject();
@@ -353,6 +365,7 @@ void ImageLoader::updateFromElement(UpdateFromElementBehavior updateBehavior, Re
 {
     AtomicString imageSourceURL = m_element->imageSourceURL();
     m_suppressErrorEvents = (updateBehavior == UpdateSizeChanged);
+    m_suppressEvents = (updateBehavior == UpdateMyReload);
 
     if (updateBehavior == UpdateIgnorePreviousError)
         clearFailedLoadURL();
@@ -365,7 +378,7 @@ void ImageLoader::updateFromElement(UpdateFromElementBehavior updateBehavior, Re
     // been requested as a main resource and ImageDocumentParser will take care of
     // funneling the main resource bytes into m_image, so just create an ImageResource
     // to be populated later.
-    if (m_loadingImageDocument && updateBehavior != UpdateForcedReload) {
+    if (m_loadingImageDocument && updateBehavior != UpdateForcedReload && updateBehavior != UpdateMyReload) {
         setImage(ImageResource::create(imageSourceToKURL(m_element->imageSourceURL())));
         m_image->setStatus(Resource::Pending);
         return;
@@ -593,6 +606,11 @@ bool ImageLoader::getImageAnimationPolicy(ImageAnimationPolicy& policy)
     return true;
 }
 
+void ImageLoader::requireReloading()
+{
+    updateFromElement(UpdateMyReload);
+}
+
 void ImageLoader::dispatchPendingLoadEvents()
 {
     loadEventSender().dispatchPendingEvents();