- 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.cc
.SetMethod("isMaximized", &Window::IsMaximized)
      .SetMethod("minimize", &Window::Minimize)
      .SetMethod("restore", &Window::Restore)
      .SetMethod("isMinimized", &Window::IsMinimized)
      .SetMethod("setFullScreen", &Window::SetFullScreen)
      .SetMethod("isFullScreen", &Window::IsFullscreen)
      .SetMethod("setAspectRatio", &Window::SetAspectRatio)
#if !defined(OS_WIN)
      .SetMethod("setParentWindow", &Window::SetParentWindow)
#endif
      .SetMethod("getParentWindow", &Window::GetParentWindow)
      .SetMethod("getChildWindows", &Window::GetChildWindows)
      .SetMethod("isModal", &Window::IsModal)
      .SetMethod("getNativeWindowHandle", &Window::GetNativeWindowHandle)
      .SetMethod("getBounds", &Window::GetBounds)
      .SetMethod("setBounds", &Window::SetBounds)
      .SetMethod("getSize", &Window::GetSize)
      .SetMethod("setSize", &Window::SetSize)
      .SetMethod("getContentBounds", &Window::GetContentBounds)
      .SetMethod("setContentBounds", &Window::SetContentBounds)
      .SetMethod("getContentSize", &Window::GetContentSize)
      .SetMethod("setContentSize", &Window::SetContentSize)
      .SetMethod("setMinimumSize", &Window::SetMinimumSize)
      .SetMethod("getMinimumSize", &Window::GetMinimumSize)
      .SetMethod("setMaximumSize", &Window::SetMaximumSize)
      .SetMethod("getMaximumSize", &Window::GetMaximumSize)
      .SetMethod("setSheetOffset", &Window::SetSheetOffset)
      .SetMethod("setResizable", &Window::SetResizable)
      .SetMethod("isResizable", &Window::IsResizable)
      .SetMethod("setMovable", &Window::SetMovable)