Resize background-attachment: fixed when inertTopControls is enabled.

third_party/WebKit/Source/core/layout/LayoutView.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc.
  *               All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 187 matching lines @@
   checkLayoutState();
 #endif
 }
 
 #if ENABLE(ASSERT)
 void LayoutView::checkLayoutState() {
   ASSERT(!m_layoutState->next());
 }
 #endif
 
-void LayoutView::setShouldDoFullPaintInvalidationOnResizeIfNeeded() {
+void LayoutView::setShouldDoFullPaintInvalidationOnResizeIfNeeded(
+    bool widthChanged,
+    bool heightChanged) {
   // When background-attachment is 'fixed', we treat the viewport (instead of
   // the 'root' i.e. html or body) as the background positioning area, and we
   // should fully invalidate on viewport resize if the background image is not
   // composited and needs full paint invalidation on background positioning area
   // resize.
   if (style()->hasFixedBackgroundImage() &&
       (!m_compositor ||
        !m_compositor->needsFixedRootBackgroundLayer(layer()))) {
-    IncludeScrollbarsInRect includeScrollbars =
-        RuntimeEnabledFeatures::rootLayerScrollingEnabled() ? IncludeScrollbars
-                                                            : ExcludeScrollbars;
-    if ((offsetWidth() != viewWidth(includeScrollbars) &&
-         mustInvalidateFillLayersPaintOnWidthChange(
-             style()->backgroundLayers())) ||
-        (offsetHeight() != viewHeight(includeScrollbars) &&
-         mustInvalidateFillLayersPaintOnHeightChange(
-             style()->backgroundLayers())))
+    if ((widthChanged && mustInvalidateFillLayersPaintOnWidthChange(
+                             style()->backgroundLayers())) ||
+        (heightChanged && mustInvalidateFillLayersPaintOnHeightChange(
+                              style()->backgroundLayers())))
       setShouldDoFullPaintInvalidation(PaintInvalidationBoundsChange);
   }
 }
 
 void LayoutView::layout() {
   if (!document().paginated())
     setPageLogicalHeight(LayoutUnit());
 
-  setShouldDoFullPaintInvalidationOnResizeIfNeeded();
+  IncludeScrollbarsInRect includeScrollbars =
+      RuntimeEnabledFeatures::rootLayerScrollingEnabled() ? IncludeScrollbars
+                                                          : ExcludeScrollbars;
+  FloatSize viewSize(frameView()->visibleContentSize(includeScrollbars));
+  setShouldDoFullPaintInvalidationOnResizeIfNeeded(
+      offsetWidth() != viewSize.width(), offsetHeight() != viewSize.height());
 
   if (pageLogicalHeight() && shouldUsePrintingLayout()) {
     m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = logicalWidth();
     if (!m_fragmentationContext) {
       m_fragmentationContext = wrapUnique(new ViewFragmentationContext(*this));
       m_paginationStateChanged = true;
     }
   } else if (m_fragmentationContext) {
     m_fragmentationContext.reset();
     m_paginationStateChanged = true;
@@ skipping 812 matching lines @@
   if (block)
     block->adjustChildDebugRect(rect);
 
   rect.setWidth(LayoutUnit(viewWidth(IncludeScrollbars)));
   rect.setHeight(LayoutUnit(viewHeight(IncludeScrollbars)));
 
   return rect;
 }
 
 }  // namespace blink