Remove the lifetime hack in ImageLoader where it keeps its assoc element alive

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 8bc2bb5869f72a265c6d8ec119e5830984e57ee2..173390c048234a4bc1438f132617d7e62cea8a7b 100644
--- a/third_party/WebKit/Source/core/loader/ImageLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/ImageLoader.cpp
@@ -147,12 +147,10 @@ private:
 
 ImageLoader::ImageLoader(Element* element)
     : m_element(element)
-    , m_derefElementTimer(this, &ImageLoader::timerFired)
     , m_hasPendingLoadEvent(false)
     , m_hasPendingErrorEvent(false)
     , m_imageComplete(true)
     , m_loadingImageDocument(false)
-    , m_elementIsProtected(false)
     , m_suppressErrorEvents(false)
 {
     RESOURCE_LOADING_DVLOG(1) << "new ImageLoader " << this;
@@ -184,10 +182,6 @@ DEFINE_TRACE(ImageLoader)
 void ImageLoader::setImage(ImageResource* newImage)
 {
     setImageWithoutConsideringPendingLoadEvent(newImage);
-
-    // Only consider updating the protection ref-count of the Element immediately before returning
-    // from this function as doing so might result in the destruction of this ImageLoader.
-    updatedHasPendingEvent();
 }
 
 void ImageLoader::setImageWithoutConsideringPendingLoadEvent(ImageResource* newImage)
@@ -343,10 +337,6 @@ void ImageLoader::doUpdateFromElement(BypassMainWorldBehavior bypassBehavior, Up
 
     if (LayoutImageResource* imageResource = layoutImageResource())
         imageResource->resetAnimation();
-
-    // Only consider updating the protection ref-count of the Element immediately before returning
-    // from this function as doing so might result in the destruction of this ImageLoader.
-    updatedHasPendingEvent();
 }
 
 void ImageLoader::updateFromElement(UpdateFromElementBehavior updateBehavior, ReferrerPolicy referrerPolicy)
@@ -466,16 +456,10 @@ void ImageLoader::imageNotifyFinished(ImageResource* resource)
         if (!m_suppressErrorEvents)
             dispatchErrorEvent();
 
-        // Only consider updating the protection ref-count of the Element immediately before returning
-        // from this function as doing so might result in the destruction of this ImageLoader.
-        updatedHasPendingEvent();
         return;
     }
     if (resource->wasCanceled()) {
         m_hasPendingLoadEvent = false;
-        // Only consider updating the protection ref-count of the Element immediately before returning
-        // from this function as doing so might result in the destruction of this ImageLoader.
-        updatedHasPendingEvent();
         return;
     }
     loadEventSender().dispatchEventSoon(this);
@@ -517,33 +501,6 @@ void ImageLoader::updateLayoutObject()
         imageResource->setImageResource(m_image.get());
 }
 
-void ImageLoader::updatedHasPendingEvent()
-{
-    // If an Element that does image loading is removed from the DOM the load/error event for the image is still observable.
-    // As long as the ImageLoader is actively loading, the Element itself needs to be ref'ed to keep it from being
-    // destroyed by DOM manipulation or garbage collection.
-    // If such an Element wishes for the load to stop when removed from the DOM it needs to stop the ImageLoader explicitly.
-    bool wasProtected = m_elementIsProtected;
-    m_elementIsProtected = m_hasPendingLoadEvent || m_hasPendingErrorEvent;
-    if (wasProtected == m_elementIsProtected)
-        return;
-
-    if (m_elementIsProtected) {
-        if (m_derefElementTimer.isActive())
-            m_derefElementTimer.stop();
-        else
-            m_keepAlive = m_element;
-    } else {
-        ASSERT(!m_derefElementTimer.isActive());
-        m_derefElementTimer.startOneShot(0, BLINK_FROM_HERE);
-    }
-}
-
-void ImageLoader::timerFired(TimerBase*)
-{
-    m_keepAlive.clear();
-}
-
 void ImageLoader::dispatchPendingEvent(ImageEventSender* eventSender)
 {
     RESOURCE_LOADING_DVLOG(1) << "ImageLoader::dispatchPendingEvent " << this;
@@ -564,10 +521,6 @@ void ImageLoader::dispatchPendingLoadEvent()
     m_hasPendingLoadEvent = false;
     if (element()->document().frame())
         dispatchLoadEvent();
-
-    // Only consider updating the protection ref-count of the Element immediately before returning
-    // from this function as doing so might result in the destruction of this ImageLoader.
-    updatedHasPendingEvent();
 }
 
 void ImageLoader::dispatchPendingErrorEvent()
@@ -578,10 +531,6 @@ void ImageLoader::dispatchPendingErrorEvent()
 
     if (element()->document().frame())
         element()->dispatchEvent(Event::create(EventTypeNames::error));
-
-    // Only consider updating the protection ref-count of the Element immediately before returning
-    // from this function as doing so might result in the destruction of this ImageLoader.
-    updatedHasPendingEvent();
 }
 
 bool ImageLoader::getImageAnimationPolicy(ImageAnimationPolicy& policy)