* 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
web_contents()->GetRenderViewHost()->GetWidget()->Focus();
}
void BrowserWindow::BlurWebView() {
  web_contents()->GetRenderViewHost()->GetWidget()->Blur();
}
bool BrowserWindow::IsWebViewFocused() {
  auto host_view = web_contents()->GetRenderViewHost()->GetWidget()->GetView();
  return host_view && host_view->HasFocus();
}
void BrowserWindow::SetRepresentedFilename(const std::string& filename) {
  window_->SetRepresentedFilename(filename);
}
std::string BrowserWindow::GetRepresentedFilename() {
  return window_->GetRepresentedFilename();
}
void BrowserWindow::SetDocumentEdited(bool edited) {
  window_->SetDocumentEdited(edited);
}
bool BrowserWindow::IsDocumentEdited() {
  return window_->IsDocumentEdited();
}
void BrowserWindow::SetIgnoreMouseEvents(bool ignore, mate::Arguments* args) {
  mate::Dictionary options;
  bool forward = false;
  args->GetNext(&options) && options.Get("forward", &forward);
  return window_->SetIgnoreMouseEvents(ignore, forward);
}
void BrowserWindow::SetContentProtection(bool enable) {