Make TopDocumentRootScrollerController store Page instead of FrameHost

third_party/WebKit/Source/core/page/scrolling/TopDocumentRootScrollerController.cpp

Index: third_party/WebKit/Source/core/page/scrolling/TopDocumentRootScrollerController.cpp
diff --git a/third_party/WebKit/Source/core/page/scrolling/TopDocumentRootScrollerController.cpp b/third_party/WebKit/Source/core/page/scrolling/TopDocumentRootScrollerController.cpp
index 412c44bd00f439e92818011b3310f3a657b1e176..bbf4c31f784cec2fb31c2d1dee55b2d10496147a 100644
--- a/third_party/WebKit/Source/core/page/scrolling/TopDocumentRootScrollerController.cpp
+++ b/third_party/WebKit/Source/core/page/scrolling/TopDocumentRootScrollerController.cpp
@@ -25,18 +25,17 @@ namespace blink {
 
 // static
 TopDocumentRootScrollerController* TopDocumentRootScrollerController::create(
-    FrameHost& host) {
-  return new TopDocumentRootScrollerController(host);
+    Page& page) {
+  return new TopDocumentRootScrollerController(page);
 }
 
-TopDocumentRootScrollerController::TopDocumentRootScrollerController(
-    FrameHost& host)
-    : m_frameHost(&host) {}
+TopDocumentRootScrollerController::TopDocumentRootScrollerController(Page& page)
+    : m_page(&page) {}
 
 DEFINE_TRACE(TopDocumentRootScrollerController) {
   visitor->trace(m_viewportApplyScroll);
   visitor->trace(m_globalRootScroller);
-  visitor->trace(m_frameHost);
+  visitor->trace(m_page);
 }
 
 void TopDocumentRootScrollerController::didChangeRootScroller() {
@@ -70,10 +69,12 @@ IntSize TopDocumentRootScrollerController::rootScrollerVisibleArea() const {
   if (!topDocument() || !topDocument()->view())
     return IntSize();
 
-  float minimumPageScale =
-      m_frameHost->pageScaleConstraintsSet().finalConstraints().minimumScale;
+  float minimumPageScale = m_page->frameHost()
+                               .pageScaleConstraintsSet()
+                               .finalConstraints()
+                               .minimumScale;
   int browserControlsAdjustment =
-      ceilf(m_frameHost->visualViewport().browserControlsAdjustment() /
+      ceilf(m_page->frameHost().visualViewport().browserControlsAdjustment() /
             minimumPageScale);
 
   return topDocument()->view()->visibleContentSize(ExcludeScrollbars) +
@@ -166,14 +167,14 @@ void TopDocumentRootScrollerController::recomputeGlobalRootScroller() {
 }
 
 Document* TopDocumentRootScrollerController::topDocument() const {
-  if (!m_frameHost)
+  if (!m_page)
     return nullptr;
 
-  if (!m_frameHost->page().mainFrame() ||
-      !m_frameHost->page().mainFrame()->isLocalFrame())
+  if (!m_page->frameHost().page().mainFrame() ||
+      !m_page->frameHost().page().mainFrame()->isLocalFrame())
     return nullptr;
 
-  return toLocalFrame(m_frameHost->page().mainFrame())->document();
+  return toLocalFrame(m_page->frameHost().page().mainFrame())->document();

[joelhockey, 2017/03/08 04:36:00]

I think these references of m_page->frameHost.page() could just be m_page

From what I can see, m_page and m_page->frameHost.page() are always the same.
I see that Page constructs a FrameHost with this
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/page/Page...
And then within FrameHost, page is not modified
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/frame/Fra...

Could the whole method be:

return m_page && m_page->mainFrame() && m_page->mainFrame().isLocalFrame()
  ? m_page->mainFrame()->document() : nullptr; 

[sashab, 2017/03/08 05:02:37]

Oh yeah, great catch! Fixed here and below, thanks.

 }
 
 void TopDocumentRootScrollerController::
@@ -194,11 +195,11 @@ void TopDocumentRootScrollerController::
 }
 
 void TopDocumentRootScrollerController::didUpdateCompositing() {
-  if (!m_frameHost)
+  if (!m_page)
     return;
 
   // Let the compositor-side counterpart know about this change.
-  m_frameHost->page().chromeClient().registerViewportLayers();
+  m_page->frameHost().page().chromeClient().registerViewportLayers();
 }
 
 void TopDocumentRootScrollerController::didDisposeScrollableArea(
@@ -223,10 +224,10 @@ void TopDocumentRootScrollerController::didDisposeScrollableArea(
 
 void TopDocumentRootScrollerController::initializeViewportScrollCallback(
     RootFrameViewport& rootFrameViewport) {
-  DCHECK(m_frameHost);
+  DCHECK(m_page);
   m_viewportApplyScroll = ViewportScrollCallback::create(
-      &m_frameHost->browserControls(), &m_frameHost->overscrollController(),
-      rootFrameViewport);
+      &m_page->frameHost().browserControls(),
+      &m_page->frameHost().overscrollController(), rootFrameViewport);
 
   recomputeGlobalRootScroller();
 }