SVG root viewport clip in paint property tree

third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/PaintPropertyTreeBuilder.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/layout/LayoutInline.h"
@@ skipping 325 matching lines @@
         return;
     const LayoutBox& box = toLayoutBox(object);
 
     // The <input> elements can't have contents thus CSS overflow property doesn't apply.
     // However for layout purposes we do generate child layout objects for them, e.g. button label.
     // We should clip the overflow from those children. This is called control clip and we
     // technically treat them like overflow clip.
     LayoutRect clipRect;
     if (box.hasControlClip()) {
         clipRect = box.controlClipRect(context.current.paintOffset);
-    } else if (box.hasOverflowClip()) {
+    } else if (box.hasOverflowClip() || (box.isSVGRoot() && toLayoutSVGRoot(box).shouldApplyViewportClip())) {
         clipRect = box.overflowClipRect(context.current.paintOffset);
     } else {
         if (ObjectPaintProperties* properties = object.getMutableForPainting().objectPaintProperties())
             properties->clearOverflowClip();
         return;
     }
 
     // This need to be in top-level block to hold the reference until we finish creating the normal clip node.
     RefPtr<ClipPaintPropertyNode> borderRadiusClip;
     if (box.styleRef().hasBorderRadius()) {
@@ skipping 198 matching lines @@
         return;
 
     updateOverflowClip(object, context);
     updatePerspective(object, context);
     updateSvgLocalToBorderBoxTransform(object, context);
     updateScrollAndScrollTranslation(object, context);
     updateOutOfFlowContext(object, context);
 }
 
 } // namespace blink