More fixes for position:fixed with root layer scrolling.

Source/core/paint/DeprecatedPaintLayerClipper.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 63 matching lines @@
     ASSERT(view);
     if (clipRects.fixed() && context.rootLayer->layoutObject() == view)
         offset -= toIntSize(view->frameView()->scrollPosition());
 
     if (layoutObject.hasOverflowClip()) {
         ClipRect newOverflowClip = toLayoutBox(layoutObject).overflowClipRect(offset, context.scrollbarRelevancy);
         newOverflowClip.setHasRadius(layoutObject.style()->hasBorderRadius());
         clipRects.setOverflowClipRect(intersection(newOverflowClip, clipRects.overflowClipRect()));
         if (layoutObject.isPositioned())
             clipRects.setPosClipRect(intersection(newOverflowClip, clipRects.posClipRect()));
+        if (layoutObject.isLayoutView())
+            clipRects.setFixedClipRect(intersection(newOverflowClip, clipRects.fixedClipRect()));
     }
 
     if (layoutObject.hasClip()) {
         LayoutRect newClip = toLayoutBox(layoutObject).clipRect(offset);
         clipRects.setPosClipRect(intersection(newClip, clipRects.posClipRect()));
         clipRects.setOverflowClipRect(intersection(newClip, clipRects.overflowClipRect()));
         clipRects.setFixedClipRect(intersection(newClip, clipRects.fixedClipRect()));
     }
 }
 
@@ skipping 286 matching lines @@
     if (context.respectOverflowClip == IgnoreOverflowClip)
         return false;
 
     if (layer->isRootLayer() && context.respectOverflowClipForViewport == IgnoreOverflowClip)
         return false;
 
     return true;
 }
 
 } // namespace blink