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 339c4a34e08392b1de941669adde04b4b49fcaf1..35b002ae04a158215f994404375ce7392bef7b12 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -430,6 +430,53 @@ 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_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_vBar->setProportion(clientHeight, contentsHeight);
+    m_vBar->offsetDidChange();
+  }
+}
+
 void FrameView::recalculateCustomScrollbarStyle() {
   bool didStyleChange = false;
   if (horizontalScrollbar() && horizontalScrollbar()->isCustomScrollbar()) {
@@ -441,7 +488,7 @@ void FrameView::recalculateCustomScrollbarStyle() {
     didStyleChange = true;
   }
   if (didStyleChange) {
-    updateScrollbarGeometry();
+    m_scrollbarManager.updateScrollbarGeometry(size());
     updateScrollCorner();
     positionScrollbarLayers();
   }
@@ -788,7 +835,7 @@ void FrameView::recalcOverflowAfterStyleChange() {
   }
 
   adjustViewSize();
-  updateScrollbarGeometry();
+  m_scrollbarManager.updateScrollbarGeometry(size());
 
   if (scrollOriginChanged())
     setNeedsLayout();
@@ -2390,6 +2437,16 @@ void FrameView::invalidatePaintForTickmarks() {
         static_cast<ScrollbarPart>(~ThumbPart));
 }
 
+void FrameView::setTickmarks(const Vector<IntRect>& tickmarks) {
+  // Tickmarks for main frame are stored in RFV.
+  if (m_frame->isMainFrame())

[bokan, 2016/11/03 19:59:59]

You'll need a similar check in getTickmarks.

[ymalik, 2016/11/04 18:54:17]

So RFV::getTickmarks calls layoutViewport().getTickmarks(). If we do the main
frame check here, we will be stuck in an infinite loop. getTickmarks is only
called from Scrollbar.cpp and this should just work since the scrollbar has the
correct ScrollableArea. 

The reason we have to call layoutViewport().getTickmarks from RFV is because RFV
doesn't have a reference to frame().document() and we can't return the default
markers from it.

The reason we have to save tickmarks in RFV (instead of just calling
layoutViewport().getTickmarks()) is because root layer scrolls has PLSA as its
layoutViewport.

+    m_viewportScrollableArea->setTickmarks(tickmarks);
+  else
+    m_tickmarks = tickmarks;
+
+  invalidatePaintForTickmarks();
+}
+
 void FrameView::getTickmarks(Vector<IntRect>& tickmarks) const {
   if (!m_tickmarks.isEmpty())
     tickmarks = m_tickmarks;
@@ -2553,6 +2610,8 @@ void FrameView::didAttachDocument() {
         RootFrameViewport::create(visualViewport, *layoutViewport);
     m_viewportScrollableArea = rootFrameViewport;
 
+    m_scrollbarManager.setScroller(rootFrameViewport);
+
     frameHost->globalRootScrollerController().initializeViewportScrollCallback(
         *rootFrameViewport);
   }
@@ -3697,12 +3756,6 @@ void FrameView::clearScrollAnchor() {
   m_scrollAnchor.clear();
 }
 
-bool FrameView::hasOverlayScrollbars() const {
-  return (horizontalScrollbar() &&
-          horizontalScrollbar()->isOverlayScrollbar()) ||
-         (verticalScrollbar() && verticalScrollbar()->isOverlayScrollbar());
-}
-
 void FrameView::computeScrollbarExistence(
     bool& newHasHorizontalScrollbar,
     bool& newHasVerticalScrollbar,
@@ -3735,15 +3788,17 @@ 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() &&
@@ -3756,48 +3811,6 @@ 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 &&
-                                      !scrollbarsHidden());
-    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 &&
-                                    !scrollbarsHidden());
-    verticalScrollbar()->setProportion(clientHeight, contentsHeight());
-    verticalScrollbar()->offsetDidChange();
-  }
-}
-
 bool FrameView::adjustScrollbarExistence(
     ComputeScrollbarExistenceOption option) {
   ASSERT(m_inUpdateScrollbars);
@@ -3900,7 +3913,7 @@ void FrameView::updateScrollbars() {
     scrollbarExistenceChanged = true;
   }
 
-  updateScrollbarGeometry();
+  m_scrollbarManager.updateScrollbarGeometry(size());
 
   if (scrollbarExistenceChanged) {
     // FIXME: Is frameRectsChanged really necessary here? Have any frame rects