- 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
return window_->IsMinimized();
}
void Window::SetFullScreen(bool fullscreen) {
  window_->SetFullScreen(fullscreen);
}
bool Window::IsFullscreen() {
  return window_->IsFullscreen();
}
void Window::SetBounds(const gfx::Rect& bounds, mate::Arguments* args) {
  bool animate = false;
  args->GetNext(&animate);
  window_->SetBounds(bounds, animate);
}
gfx::Rect Window::GetBounds() {
  return window_->GetBounds();
}
void Window::SetContentBounds(const gfx::Rect& bounds, mate::Arguments* args) {
  bool animate = false;
  args->GetNext(&animate);
  window_->SetContentBounds(bounds, animate);
}
gfx::Rect Window::GetContentBounds() {
  return window_->GetContentBounds();
}
void Window::SetSize(int width, int height, mate::Arguments* args) {
  bool animate = false;
  args->GetNext(&animate);
  window_->SetSize(gfx::Size(width, height), animate);
}
std::vector<int> Window::GetSize() {