MainFrame scrollbars should work with RFV instead of FV

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

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index 3c7a5ca233b60d503615bf953f2fe86955b68b4a..27a478a299d7fd1ba324e86015782fc15fcc17ff 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -439,6 +439,55 @@ void FrameView::ScrollbarManager::destroyScrollbar(
   scrollbar = nullptr;
 }
 
+ScrollableArea* FrameView::ScrollbarManager::scrollableArea() const {
+  return m_scrollableArea.get();
+}
+
+void FrameView::ScrollbarManager::updateScrollbarGeometry(IntSize viewSize) {
+  if (!hasHorizontalScrollbar() && !hasVerticalScrollbar())
+    return;
+
+  bool scrollbarOnLeft = m_scrollableArea->shouldPlaceVerticalScrollbarOnLeft();
+
+  if (hasHorizontalScrollbar()) {
+    int thickness = m_hBar->scrollbarThickness();
+    IntRect oldRect(m_hBar->frameRect());
+    IntRect hBarRect(
+        (scrollbarOnLeft && hasVerticalScrollbar()) ? m_vBar->width() : 0,
+        viewSize.height() - thickness,
+        viewSize.width() - (hasVerticalScrollbar() ? m_vBar->width() : 0),
+        thickness);
+    m_hBar->setFrameRect(hBarRect);
+    if (oldRect != m_hBar->frameRect())
+      m_scrollableArea->setScrollbarNeedsPaintInvalidation(HorizontalScrollbar);
+
+    int visibleWidth = m_scrollableArea->visibleWidth();
+    int contentsWidth = m_scrollableArea->contentsSize().width();
+    m_hBar->setEnabled(contentsWidth > visibleWidth &&
+                       !m_scrollableArea->scrollbarsHidden());
+    m_hBar->setProportion(visibleWidth, contentsWidth);
+    m_hBar->offsetDidChange();
+  }
+
+  if (hasVerticalScrollbar()) {
+    int thickness = m_vBar->scrollbarThickness();
+    IntRect oldRect(m_vBar->frameRect());
+    IntRect vBarRect(
+        scrollbarOnLeft ? 0 : (viewSize.width() - thickness), 0, thickness,
+        viewSize.height() - (hasHorizontalScrollbar() ? m_hBar->height() : 0));
+    m_vBar->setFrameRect(vBarRect);
+    if (oldRect != m_vBar->frameRect())
+      m_scrollableArea->setScrollbarNeedsPaintInvalidation(VerticalScrollbar);
+
+    int clientHeight = m_scrollableArea->visibleHeight();
+    int contentsHeight = m_scrollableArea->contentsSize().height();
+    m_vBar->setEnabled(contentsHeight > clientHeight &&
+                       !m_scrollableArea->scrollbarsHidden());
+    m_vBar->setProportion(clientHeight, contentsHeight);
+    m_vBar->offsetDidChange();
+  }
+}
+
 void FrameView::recalculateCustomScrollbarStyle() {
   bool didStyleChange = false;
   if (horizontalScrollbar() && horizontalScrollbar()->isCustomScrollbar()) {
@@ -450,7 +499,7 @@ void FrameView::recalculateCustomScrollbarStyle() {
     didStyleChange = true;
   }
   if (didStyleChange) {
-    updateScrollbarGeometry();
+    m_scrollbarManager.updateScrollbarGeometry(size());
     updateScrollCorner();
     positionScrollbarLayers();
   }
@@ -797,7 +846,7 @@ void FrameView::recalcOverflowAfterStyleChange() {
   }
 
   adjustViewSize();
-  updateScrollbarGeometry();
+  m_scrollbarManager.updateScrollbarGeometry(size());
 
   if (scrollOriginChanged())
     setNeedsLayout();
@@ -2413,7 +2462,7 @@ bool FrameView::isActive() const {
 }
 
 void FrameView::invalidatePaintForTickmarks() {
-  if (Scrollbar* scrollbar = verticalScrollbar())
+  if (Scrollbar* scrollbar = getScrollableArea()->verticalScrollbar())
     scrollbar->setNeedsPaintInvalidation(
         static_cast<ScrollbarPart>(~ThumbPart));
 }
@@ -2581,6 +2630,13 @@ void FrameView::didAttachDocument() {
         RootFrameViewport::create(visualViewport, *layoutViewport);
     m_viewportScrollableArea = rootFrameViewport;
 
+    // TODO(crbug.com/661236): Currently for the main frame, the scroller that
+    // the scrollbar manager works with is RootFrameViewport which is needed so
+    // that the visual viewport is taken into account when determining scrollbar
+    // extent and existence. Eventually, each scroller should have its own
+    // scrollbar manager and we shouldn't set the scroller here.
+    m_scrollbarManager.setScroller(rootFrameViewport);
+
     frameHost->globalRootScrollerController().initializeViewportScrollCallback(
         *rootFrameViewport);
   }
@@ -3714,12 +3770,6 @@ void FrameView::clearScrollAnchor() {
   m_scrollAnchor.clear();
 }
 
-bool FrameView::hasOverlayScrollbars() const {
-  return (horizontalScrollbar() &&
-          horizontalScrollbar()->isOverlayScrollbar()) ||
-         (verticalScrollbar() && verticalScrollbar()->isOverlayScrollbar());
-}
-
 void FrameView::computeScrollbarExistence(
     bool& newHasHorizontalScrollbar,
     bool& newHasVerticalScrollbar,
@@ -3752,15 +3802,17 @@ void FrameView::computeScrollbarExistence(
       (hScroll != ScrollbarAuto && vScroll != ScrollbarAuto))
     return;
 
+  ScrollableArea* scroller = m_scrollbarManager.scrollableArea();
   if (hScroll == ScrollbarAuto)
-    newHasHorizontalScrollbar = docSize.width() > visibleWidth();
+    newHasHorizontalScrollbar = docSize.width() > scroller->visibleWidth();
   if (vScroll == ScrollbarAuto)
-    newHasVerticalScrollbar = docSize.height() > visibleHeight();
+    newHasVerticalScrollbar = docSize.height() > scroller->visibleHeight();
 
   if (hasOverlayScrollbars())
     return;
 
-  IntSize fullVisibleSize = visibleContentRect(IncludeScrollbars).size();
+  IntSize fullVisibleSize =
+      scroller->visibleContentRect(IncludeScrollbars).size();
 
   bool attemptToRemoveScrollbars =
       (option == FirstPass && docSize.width() <= fullVisibleSize.width() &&
@@ -3773,46 +3825,6 @@ void FrameView::computeScrollbarExistence(
   }
 }
 
-void FrameView::updateScrollbarGeometry() {
-  if (horizontalScrollbar()) {
-    int thickness = horizontalScrollbar()->scrollbarThickness();
-    int clientWidth = visibleWidth();
-    IntRect oldRect(horizontalScrollbar()->frameRect());
-    IntRect hBarRect(
-        (shouldPlaceVerticalScrollbarOnLeft() && verticalScrollbar())
-            ? verticalScrollbar()->width()
-            : 0,
-        height() - thickness,
-        width() - (verticalScrollbar() ? verticalScrollbar()->width() : 0),
-        thickness);
-    horizontalScrollbar()->setFrameRect(hBarRect);
-    if (oldRect != horizontalScrollbar()->frameRect())
-      setScrollbarNeedsPaintInvalidation(HorizontalScrollbar);
-
-    horizontalScrollbar()->setEnabled(contentsWidth() > clientWidth);
-    horizontalScrollbar()->setProportion(clientWidth, contentsWidth());
-    horizontalScrollbar()->offsetDidChange();
-  }
-
-  if (verticalScrollbar()) {
-    int thickness = verticalScrollbar()->scrollbarThickness();
-    int clientHeight = visibleHeight();
-    IntRect oldRect(verticalScrollbar()->frameRect());
-    IntRect vBarRect(
-        shouldPlaceVerticalScrollbarOnLeft() ? 0 : (width() - thickness), 0,
-        thickness,
-        height() -
-            (horizontalScrollbar() ? horizontalScrollbar()->height() : 0));
-    verticalScrollbar()->setFrameRect(vBarRect);
-    if (oldRect != verticalScrollbar()->frameRect())
-      setScrollbarNeedsPaintInvalidation(VerticalScrollbar);
-
-    verticalScrollbar()->setEnabled(contentsHeight() > clientHeight);
-    verticalScrollbar()->setProportion(clientHeight, contentsHeight());
-    verticalScrollbar()->offsetDidChange();
-  }
-}
-
 bool FrameView::adjustScrollbarExistence(
     ComputeScrollbarExistenceOption option) {
   ASSERT(m_inUpdateScrollbars);
@@ -3911,7 +3923,7 @@ void FrameView::updateScrollbars() {
     scrollbarExistenceChanged = true;
   }
 
-  updateScrollbarGeometry();
+  m_scrollbarManager.updateScrollbarGeometry(size());
 
   if (scrollbarExistenceChanged) {
     // FIXME: Is frameRectsChanged really necessary here? Have any frame rects