Invalidate scrollbars when window activity changes if needed

third_party/WebKit/Source/platform/scroll/Scrollbar.cpp

 /*
  * Copyright (C) 2004, 2006, 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 487 matching lines @@
 }
 
 bool Scrollbar::shouldParticipateInHitTesting()
 {
     // Non-overlay scrollbars should always participate in hit testing.
     if (!isOverlayScrollbar())
         return true;
     return m_scrollableArea->scrollAnimator()->shouldScrollbarParticipateInHitTesting(this);
 }
 
+void Scrollbar::windowActiveChanged()
+{
+    if (m_theme && m_theme->invalidateOnWindowActiveChange())
+        invalidate();
+}
+
 bool Scrollbar::isWindowActive() const
 {
     return m_scrollableArea && m_scrollableArea->isActive();
 }
 
 void Scrollbar::invalidateRect(const IntRect& rect)
 {
     if (suppressInvalidation())
         return;
 
@@ skipping 38 matching lines @@
     if (!m_scrollableArea)
         return 0;
 
     if (m_orientation == HorizontalScrollbar)
         return m_scrollableArea->scrollPosition().x() - m_scrollableArea->minimumScrollPosition().x();
 
     return m_scrollableArea->scrollPosition().y() - m_scrollableArea->minimumScrollPosition().y();
 }
 
 } // namespace blink