* Electron version: 1.8.2
* Operating system: macos 10.13.3

Reproducing repo: https://github.com/ibash/electron-webkit-app-drag

Demonstrates a bug where `-webkit-app-region: drag` causes a browser view in front of it to miss click events. Oddly - it does not prevent hover events.

Steps:
1. Clone https://github.com/ibash/electron-webkit-app-drag, `yarn install`, `yarn start`
2. Click "button1"
3. Click "button2"

Expected:

Clicking button1 or button2 pops up an alert: "button clicked!"

Actual:

Only clicking button2 pops up an alert: "button clicked!"

atom/browser/api/atom_api_browser_window.cc
window_->Maximize();
}
void BrowserWindow::Unmaximize() {
  window_->Unmaximize();
}
bool BrowserWindow::IsMaximized() {
  return window_->IsMaximized();
}
void BrowserWindow::Minimize() {
  window_->Minimize();
}
void BrowserWindow::Restore() {
  window_->Restore();
}
bool BrowserWindow::IsMinimized() {
  return window_->IsMinimized();
}
void BrowserWindow::SetFullScreen(bool fullscreen) {
  window_->SetFullScreen(fullscreen);
}
bool BrowserWindow::IsFullscreen() {
  return window_->IsFullscreen();
}
void BrowserWindow::SetBounds(const gfx::Rect& bounds, mate::Arguments* args) {
  bool animate = false;
  args->GetNext(&animate);
  window_->SetBounds(bounds, animate);
}
gfx::Rect BrowserWindow::GetBounds() {