Migrate wheel events to EventHandlerRegistry

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index 1a4e1347d9ad6369c6192253ed2a42b385cbc654..aa1a9cb6b2584883700da33702b4a45d86a302b5 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -39,13 +39,13 @@
 #include "core/dom/Document.h"
 #include "core/dom/DocumentMarkerController.h"
 #include "core/dom/Text.h"
-#include "core/dom/WheelController.h"
 #include "core/editing/Editor.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/InputMethodController.h"
 #include "core/editing/TextIterator.h"
 #include "core/events/KeyboardEvent.h"
 #include "core/events/WheelEvent.h"
+#include "core/frame/EventHandlerRegistry.h"
 #include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
@@ -1476,18 +1476,14 @@ void WebViewImpl::popupOpened(PopupContainer* popupContainer)
 {
     ASSERT(!m_selectPopup);
     m_selectPopup = popupContainer;
-    ASSERT(mainFrameImpl()->frame()->document());
-    Document& document = *mainFrameImpl()->frame()->document();
-    WheelController::from(document)->didAddWheelEventHandler(document);
+    page()->frameHost().eventHandlerRegistry().didAddExternalEventHandler(EventTypeNames::wheel);

[Rick Byers, 2014/05/31 03:16:40]

I know you're just updating the existing code, but this seems fishy.  I wonder
why it's necessary.  Seems unfortunate to add the external event handler
mechanism just for this (but there was something else we needed it for right?). 
Anyway it's probably not necessary to dig into it now.

[Sami, 2014/06/02 10:00:22]

This is the only place where we need external event handlers :( Looks like this
is here to make sure popup windows are closed when you scroll:
https://chromiumcodereview.appspot.com/23677012. It feels like we should instead
close the popups as a response to a changing scroll offset -- but that could
have other side-effects.

 }
 
 void WebViewImpl::popupClosed(PopupContainer* popupContainer)
 {
     ASSERT(m_selectPopup);
     m_selectPopup = nullptr;
-    ASSERT(mainFrameImpl()->frame()->document());
-    Document& document = *mainFrameImpl()->frame()->document();
-    WheelController::from(document)->didRemoveWheelEventHandler(document);
+    page()->frameHost().eventHandlerRegistry().didRemoveExternalEventHandler(EventTypeNames::wheel);
 }
 
 PagePopup* WebViewImpl::openPagePopup(PagePopupClient* client, const IntRect& originBoundsInRootView)