Don't composite layers with an invisible frameview.

third_party/WebKit/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 3783 matching lines @@
     // Scrollbars won't be transformed within us
     newPoint.moveBy(-scrollbar.location());
     return newPoint;
 }
 
 void FrameView::setParentVisible(bool visible)
 {
     if (isParentVisible() == visible)
         return;
 
+    // As parent visibility changes, we may need to recomposite this frame view and potentially child frame views.
+    if (PaintLayerCompositor* compositor = layoutView() ? layoutView()->compositor() : nullptr)
+        compositor->setNeedsCompositingUpdate(CompositingUpdateRebuildTree);
+
     Widget::setParentVisible(visible);
 
     if (!isSelfVisible())
         return;
 
     for (const auto& child : m_children)
         child->setParentVisible(visible);
 }
 
 void FrameView::show()
 {
     if (!isSelfVisible()) {
         setSelfVisible(true);
         updateScrollableAreaSet();
         if (isParentVisible()) {
-            for (const auto& child : m_children)
+            for (const auto& child : m_children) {

[chrishtr, 2016/01/28 00:32:31]

Remove curlies.

[wkorman, 2016/01/28 00:55:21]

Done.

                 child->setParentVisible(true);
+            }
         }
     }
 
     Widget::show();
 }
 
 void FrameView::hide()
 {
     if (isSelfVisible()) {
         if (isParentVisible()) {
@@ skipping 219 matching lines @@
     return m_hiddenForThrottling && m_crossOriginForThrottling;
 }
 
 LayoutBox& FrameView::boxForScrollControlPaintInvalidation() const
 {
     ASSERT(layoutView());
     return *layoutView();
 }
 
 } // namespace blink