- Electron version: v1.3.3
- Operating system: OS X 10.11.6

v1.3.3 broke the detection of the `scroll-touch-begin` and `scroll-touch-end` events for me within a `webview`. It looks like the pull request #6754 caused this issue. v1.3.2 works as expected.

Behavior that I'm observing on v1.3.3:
- Most of the time, the `scroll-touch-*` events are not emitted when the cursor is on top of a `webview`.
- The `scroll-touch-*` events seem to be emitted _only once_ when the cursor is on a `webview` and on a scrollable element. The scrollable elements in my app have no native scrollbar set (they have the style `overflow: hidden;` set instead of `overflow: scroll;`). This is the case in which I need to receive the `scroll-touch-*` events.
- The `scroll-touch-*` events seem to work fine when the cursor is outside of the `webview` tag.

atom/browser/api/atom_api_window.h
bool IsMenuBarVisible();
  void SetAspectRatio(double aspect_ratio, mate::Arguments* args);
  void SetParentWindow(v8::Local<v8::Value> value, mate::Arguments* args);
  v8::Local<v8::Value> GetParentWindow() const;
  std::vector<v8::Local<v8::Object>> GetChildWindows() const;
  bool IsModal() const;
  v8::Local<v8::Value> GetNativeWindowHandle();
#if defined(OS_WIN)
  typedef base::Callback<void(v8::Local<v8::Value>,
                              v8::Local<v8::Value>)> MessageCallback;
  bool HookWindowMessage(UINT message, const MessageCallback& callback);
  bool IsWindowMessageHooked(UINT message);
  void UnhookWindowMessage(UINT message);
  void UnhookAllWindowMessages();
  bool SetThumbnailClip(const gfx::Rect& region);
  bool SetThumbnailToolTip(const std::string& tooltip);
#endif
#if defined(TOOLKIT_VIEWS)
  void SetIcon(mate::Handle<NativeImage> icon);
#endif
  void SetVisibleOnAllWorkspaces(bool visible);
  bool IsVisibleOnAllWorkspaces();
  int32_t ID() const;
  v8::Local<v8::Value> WebContents(v8::Isolate* isolate);
  
  void RemoveFromParentChildWindows();
#if defined(OS_WIN)
  typedef std::map<UINT, MessageCallback> MessageCallbackMap;
  MessageCallbackMap messages_callback_map_;
#endif