Pass implementation object to supplemental classes by reference

Source/core/page/scrolling/ScrollingCoordinator.cpp

Index: Source/core/page/scrolling/ScrollingCoordinator.cpp
diff --git a/Source/core/page/scrolling/ScrollingCoordinator.cpp b/Source/core/page/scrolling/ScrollingCoordinator.cpp
index 76571fb19d2d4e2d7dda439c9161f63f285b1544..63770190871854ef349ed62505eec983d38a7b6d 100644
--- a/Source/core/page/scrolling/ScrollingCoordinator.cpp
+++ b/Source/core/page/scrolling/ScrollingCoordinator.cpp
@@ -799,7 +799,7 @@ unsigned ScrollingCoordinator::computeCurrentWheelEventHandlerCount()
 
     for (Frame* frame = m_page->mainFrame(); frame; frame = frame->tree().traverseNext()) {
         if (frame->document())
-            wheelEventHandlerCount += WheelController::from(frame->document())->wheelEventHandlerCount();
+            wheelEventHandlerCount += WheelController::from(*frame->document())->wheelEventHandlerCount();
     }
 
     return wheelEventHandlerCount;