diff --git a/Source/WebCore/platform/ScrollView.cpp b/Source/WebCore/platform/ScrollView.cpp
index ddede65..1906ba3 100644
--- a/Source/WebCore/platform/ScrollView.cpp
+++ b/Source/WebCore/platform/ScrollView.cpp
@@ -996,10 +996,12 @@
     if (platformWidget())
         return 0;
 
-    IntPoint viewPoint = convertFromContainingWindow(windowPoint);
-    if (m_horizontalScrollbar && m_horizontalScrollbar->shouldParticipateInHitTesting() && m_horizontalScrollbar->frameRect().contains(viewPoint))
+    // convertFromContainingWindow doesn't do what it sounds like it does. We need it here just to get this
+    // point into the right coordinates if this is the ScrollView of a sub-frame.
+    IntPoint convertedPoint = convertFromContainingWindow(windowPoint);
+    if (m_horizontalScrollbar && m_horizontalScrollbar->shouldParticipateInHitTesting() && m_horizontalScrollbar->frameRect().contains(convertedPoint))
         return m_horizontalScrollbar.get();
-    if (m_verticalScrollbar && m_verticalScrollbar->shouldParticipateInHitTesting() && m_verticalScrollbar->frameRect().contains(viewPoint))
+    if (m_verticalScrollbar && m_verticalScrollbar->shouldParticipateInHitTesting() && m_verticalScrollbar->frameRect().contains(convertedPoint))
         return m_verticalScrollbar.get();
     return 0;
 }