Raise the loading priority of in-viewport images.

Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 19 matching lines @@
 #include "HTMLNames.h"
 #include "RuntimeEnabledFeatures.h"
 #include "core/accessibility/AXObjectCache.h"
 #include "core/animation/DocumentAnimations.h"
 #include "core/css/FontFaceSet.h"
 #include "core/css/resolver/StyleResolver.h"
 #include "core/dom/DocumentMarkerController.h"
 #include "core/editing/FrameSelection.h"
 #include "core/events/OverflowEvent.h"
 #include "core/fetch/ResourceFetcher.h"
+#include "core/fetch/ResourceLoadPriorityOptimizer.h"
 #include "core/fetch/TextResourceDecoder.h"
 #include "core/html/HTMLFrameElement.h"
 #include "core/html/HTMLHtmlElement.h"
 #include "core/html/HTMLPlugInElement.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/Chrome.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/EventHandler.h"
@@ skipping 836 matching lines @@
         forceLayoutParentViewIfNeeded();
 
         // Text Autosizing requires two-pass layout which is incompatible with partial layout.
         // If enabled, only do partial layout for the second layout.
         // FIXME (crbug.com/256657): Do not do two layouts for text autosizing.
         PartialLayoutDisabler partialLayoutDisabler(partialLayout(), m_frame->settings() && m_frame->settings()->textAutosizingEnabled());
 
         LayoutIndicator layoutIndicator;
         rootForThisLayout->layout();
         gatherDebugLayoutRects(rootForThisLayout);
+
+        ResourceLoadPriorityOptimizer modifier;
+        rootForThisLayout->didLayout(modifier);
     }
 
     TextAutosizer* textAutosizer = frame().document()->textAutosizer();
     bool autosized = textAutosizer && textAutosizer->processSubtree(rootForThisLayout);
     if (autosized && rootForThisLayout->needsLayout()) {
         TRACE_EVENT0("webkit", "2nd layout due to Text Autosizing");
         LayoutIndicator layoutIndicator;
         rootForThisLayout->layout();
         gatherDebugLayoutRects(rootForThisLayout);
+
+        ResourceLoadPriorityOptimizer modifier;
+        rootForThisLayout->didLayout(modifier);
     }
 
     m_inLayout = false;
 
     if (inSubtreeLayout)
         rootForThisLayout->view()->popLayoutState(rootForThisLayout);
 }
 
 void FrameView::scheduleOrPerformPostLayoutTasks()
 {
@@ skipping 748 matching lines @@
 
 void FrameView::scrollPositionChanged()
 {
     m_frame->eventHandler().sendScrollEvent();
     m_frame->eventHandler().dispatchFakeMouseMoveEventSoon();
 
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
             renderView->compositor()->frameViewDidScroll();
     }
+
+    if (m_frame->document() && m_frame->document()->renderer()) {

[shatch, 2013/12/07 03:16:15]

There was a crash on mac on FrameView::scrollPositionChanged during destruction
of a FrameView. Couldn't reproduce it locally on linux (don't have a mac), so I
forced a scrollPositionChanged from the destructor of FrameView and ended up
crashing with a NULL renderer() from m_frame->document()->renderer(), so added
checks in here.

+        ResourceLoadPriorityOptimizer modifier;
+        m_frame->document()->renderer()->didScroll(modifier);
+    }
 }
 
 void FrameView::repaintFixedElementsAfterScrolling()
 {
     // For fixed position elements, update widget positions and compositing layers after scrolling,
     // but only if we're not inside of layout.
     if (!m_nestedLayoutCount && hasViewportConstrainedObjects()) {
         if (RenderView* renderView = this->renderView()) {
             renderView->updateWidgetPositions();
             renderView->layer()->updateLayerPositionsAfterDocumentScroll();
@@ skipping 1797 matching lines @@
 void FrameView::willRemoveScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::willRemoveScrollbar(scrollbar, orientation);
     if (AXObjectCache* cache = axObjectCache()) {
         cache->remove(scrollbar);
         cache->handleScrollbarUpdate(this);
     }
 }
 
 } // namespace WebCore