Fix frame coordinate translation issue with scroll views.

third_party/WebKit/Source/web/WebInputEventConversion.cpp

 /*
  * Copyright (C) 2009 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 183 matching lines @@
   return TransformWebTouchEvent(frameScale(frameViewBase),
                                 frameTranslation(frameViewBase), event);
 }
 
 WebMouseEventBuilder::WebMouseEventBuilder(const FrameViewBase* frameViewBase,
                                            const LayoutItem layoutItem,
                                            const MouseEvent& event) {
   if (event.nativeEvent()) {
     *static_cast<WebMouseEvent*>(this) =
         event.nativeEvent()->flattenTransform();
-    WebFloatPoint absoluteRootFrameLocation = positionInRootFrame();
+    WebFloatPoint absoluteLocation = positionInRootFrame();
+
+    FrameView* view = frameViewBase ? toFrameView(frameViewBase->parent()) : 0;
+
+    // Translate the root frame position to content coordinates.
+    if (view) {
+      absoluteLocation = view->rootFrameToContents(absoluteLocation);
+    }
+
     IntPoint localPoint = roundedIntPoint(
-        layoutItem.absoluteToLocal(absoluteRootFrameLocation, UseTransforms));
+        layoutItem.absoluteToLocal(absoluteLocation, UseTransforms));
     x = localPoint.x();
     y = localPoint.y();
     return;
   }
 
   // Code below here can be removed once OOPIF ships.
   // OOPIF will prevent synthetic events being dispatched into
   // other frames; but for now we allow the fallback to generate
   // WebMouseEvents from synthetic events.
   if (event.type() == EventTypeNames::mousemove)
@@ skipping 153 matching lines @@
   Vector<WebTouchEvent> result;
   for (const auto& event : coalescedEvents) {
     DCHECK(WebInputEvent::isTouchEventType(event->type()));
     result.push_back(TransformWebTouchEvent(
         scale, translation, static_cast<const WebTouchEvent&>(*event)));
   }
   return result;
 }
 
 }  // namespace blink