Properly calculate the localBounds for elements with overflow clipped

third_party/WebKit/Source/core/layout/ScrollAnchor.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/layout/ScrollAnchor.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/UseCounter.h"
 #include "core/layout/line/InlineTextBox.h"
 #include "core/paint/PaintLayerScrollableArea.h"
@@ skipping 61 matching lines @@
     ASSERT_NOT_REACHED();
     return LayoutPoint();
 }
 
 // Bounds of the LayoutObject relative to the scroller's visible content rect.
 static LayoutRect relativeBounds(const LayoutObject* layoutObject, const ScrollableArea* scroller)
 {
     LayoutRect localBounds;
     if (layoutObject->isBox()) {
         localBounds = toLayoutBox(layoutObject)->borderBoxRect();
-        // borderBoxRect doesn't include overflow content and floats.
-        LayoutUnit maxHeight = std::max(localBounds.height(), toLayoutBox(layoutObject)->layoutOverflowRect().height());
-        if (layoutObject->isLayoutBlockFlow() && toLayoutBlockFlow(layoutObject)->containsFloats()) {
-            // Note that lowestFloatLogicalBottom doesn't include floating
-            // grandchildren.
-            maxHeight = std::max(maxHeight, toLayoutBlockFlow(layoutObject)->lowestFloatLogicalBottom());
+        if (!layoutObject->hasOverflowClip()) {
+            // borderBoxRect doesn't include overflow content and floats.
+            LayoutUnit maxHeight = std::max(localBounds.height(), toLayoutBox(layoutObject)->layoutOverflowRect().height());
+            if (layoutObject->isLayoutBlockFlow() && toLayoutBlockFlow(layoutObject)->containsFloats()) {
+                // Note that lowestFloatLogicalBottom doesn't include floating
+                // grandchildren.
+                maxHeight = std::max(maxHeight, toLayoutBlockFlow(layoutObject)->lowestFloatLogicalBottom());
+            }
+            localBounds.setHeight(maxHeight);
         }
-        localBounds.setHeight(maxHeight);
     } else if (layoutObject->isText()) {
         // TODO(skobes): Use first and last InlineTextBox only?
         for (InlineTextBox* box = toLayoutText(layoutObject)->firstTextBox(); box; box = box->nextTextBox())
             localBounds.unite(box->calculateBoundaries());
     } else {
         // Only LayoutBox and LayoutText are supported.
         ASSERT_NOT_REACHED();
     }
     LayoutRect relativeBounds = LayoutRect(layoutObject->localToAncestorQuad(
         FloatRect(localBounds), scrollerLayoutBox(scroller)).boundingBox());
@@ skipping 208 matching lines @@
 
 void ScrollAnchor::notifyRemoved(LayoutObject* layoutObject)
 {
     if (m_current.m_anchorObject == layoutObject)
         m_current.clear();
     if (m_lastAdjusted.m_anchorObject == layoutObject)
         m_lastAdjusted.clear();
 }
 
 } // namespace blink