Defer call to updateWidgetPositions() outside of RenderLayerScrollableArea.

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 103 matching lines @@
     , m_isTrackingPaintInvalidations(false)
     , m_scrollCorner(nullptr)
     , m_shouldAutoSize(false)
     , m_inAutoSize(false)
     , m_didRunAutosize(false)
     , m_hasSoftwareFilters(false)
     , m_visibleContentScaleFactor(1)
     , m_inputEventsScaleFactorForEmulation(1)
     , m_layoutSizeFixedToFrameSize(true)
     , m_didScrollTimer(this, &FrameView::didScrollTimerFired)
+    , m_needsUpdateWidgetPositions(false)
 {
     ASSERT(m_frame);
     init();
 
     if (!m_frame->isMainFrame())
         return;
 
     ScrollableArea::setVerticalScrollElasticity(ScrollElasticityAllowed);
     ScrollableArea::setHorizontalScrollElasticity(ScrollElasticityAllowed);
 }
@@ skipping 2507 matching lines @@
         return;
 
     if (m_frame->isMainFrame()) {
         if (m_frame->page()->chrome().client().paintCustomOverhangArea(context, horizontalOverhangArea, verticalOverhangArea, dirtyRect))
             return;
     }
 
     ScrollView::paintOverhangAreas(context, horizontalOverhangArea, verticalOverhangArea, dirtyRect);
 }
 
+void FrameView::updateWidgetPositionsIfNeeded()
+{
+    if (!m_needsUpdateWidgetPositions)
+        return;
+
+    m_needsUpdateWidgetPositions = false;
+
+    updateWidgetPositions();
+}
+
 void FrameView::updateLayoutAndStyleForPainting()
 {
     // Updating layout can run script, which can tear down the FrameView.
     RefPtr<FrameView> protector(this);
 
     updateLayoutAndStyleIfNeededRecursive();
 
+    updateWidgetPositionsIfNeeded();
+
     if (RenderView* view = renderView()) {
         TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "UpdateLayerTree", "frame", m_frame.get());
         // FIXME(361045): remove InspectorInstrumentation calls once DevTools Timeline migrates to tracing.
         InspectorInstrumentation::willUpdateLayerTree(m_frame.get());
 
         view->compositor()->updateIfNeededRecursive();
 
         if (view->compositor()->inCompositingMode() && m_frame->isLocalRoot())
             m_frame->page()->scrollingCoordinator()->updateAfterCompositingChangeIfNeeded();
 
@@ skipping 463 matching lines @@
 void FrameView::willRemoveScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::willRemoveScrollbar(scrollbar, orientation);
     if (AXObjectCache* cache = axObjectCache()) {
         cache->remove(scrollbar);
         cache->handleScrollbarUpdate(this);
     }
 }
 
 } // namespace blink