Implementing document.setRootScroller API for main thread scrolling.

third_party/WebKit/Source/core/frame/FrameHost.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 20 matching lines @@
 #include "core/frame/FrameHost.h"
 
 #include "core/frame/EventHandlerRegistry.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/PageScaleConstraints.h"
 #include "core/frame/PageScaleConstraintsSet.h"
 #include "core/frame/TopControls.h"
 #include "core/inspector/ConsoleMessageStorage.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/OverscrollController.h"
+#include "core/page/scrolling/RootScroller.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebScheduler.h"
 
 namespace blink {
 
 FrameHost* FrameHost::create(Page& page)
 {
     return new FrameHost(page);
 }
 
 FrameHost::FrameHost(Page& page)
     : m_page(&page)
+    , m_rootScroller(RootScroller::create(*this))
     , m_topControls(TopControls::create(*this))
     , m_pageScaleConstraintsSet(PageScaleConstraintsSet::create())
     , m_visualViewport(VisualViewport::create(*this))
     , m_overscrollController(OverscrollController::create(
         *m_visualViewport,
         m_page->chromeClient()))
     , m_eventHandlerRegistry(new EventHandlerRegistry(*this))
     , m_consoleMessageStorage(ConsoleMessageStorage::create())
     , m_subframeCount(0)
 {
@@ skipping 52 matching lines @@
 const Deprecation& FrameHost::deprecation() const
 {
     return m_page->deprecation();
 }
 
 float FrameHost::deviceScaleFactor() const
 {
     return m_page->deviceScaleFactor();
 }
 
+RootScroller* FrameHost::rootScroller()
+{
+    // RootScroller only makes sense if we're in the process where the main
+    // frame is local.
+    if (!m_page->mainFrame() || !m_page->mainFrame()->isLocalFrame())
+        return nullptr;
+
+    return m_rootScroller;
+}
+
+const RootScroller* FrameHost::rootScroller() const
+{
+    // RootScroller only makes sense if we're in the process where the main
+    // frame is local.
+    if (!m_page->mainFrame() || !m_page->mainFrame()->isLocalFrame())
+        return nullptr;
+
+    return m_rootScroller;
+}
+
 TopControls& FrameHost::topControls()
 {
     return *m_topControls;
 }
 
 const TopControls& FrameHost::topControls() const
 {
     return *m_topControls;
 }
 
@@ skipping 43 matching lines @@
 }
 
 const ConsoleMessageStorage& FrameHost::consoleMessageStorage() const
 {
     return *m_consoleMessageStorage;
 }
 
 DEFINE_TRACE(FrameHost)
 {
     visitor->trace(m_page);
+    visitor->trace(m_rootScroller);
     visitor->trace(m_topControls);
     visitor->trace(m_visualViewport);
     visitor->trace(m_overscrollController);
     visitor->trace(m_eventHandlerRegistry);
     visitor->trace(m_consoleMessageStorage);
 }
 
 #if ENABLE(ASSERT)
 void checkFrameCountConsistency(int expectedFrameCount, Frame* frame)
 {
@@ skipping 51 matching lines @@
 
     FrameView* rootView = page().deprecatedLocalMainFrame()->view();
 
     if (!rootView)
         return;
 
     rootView->setNeedsLayout();
 }
 
 } // namespace blink