* Output of `node_modules/.bin/electron --version`: v5.0.0-nightly.20190107
* Operating System (Platform and Version): macOS Mojave 10.14.2 (18C54)
* Output of `node_modules/.bin/electron --version` on last known working Electron version (if applicable): never

**Expected Behavior**
Using navigator.mediaDevices.getDisplayMedia({ video: true }), a native screen picker should appear.

**Actual behavior**
The following error is thrown: NotAllowedError: Permission denied

**Screenshots**
Expected dialog
![image](https://user-images.githubusercontent.com/1120050/51625551-71736500-1f0b-11e9-9a95-1406cad95046.png)
atom/browser/atom_browser_client.cc
PWSTR current_app_id;
  if (SUCCEEDED(GetCurrentProcessExplicitAppUserModelID(&current_app_id))) {
    command_line->AppendSwitchNative(switches::kAppUserModelId, current_app_id);
    CoTaskMemFree(current_app_id);
  }
#endif
  if (delegate_) {
    auto app_path = static_cast<api::App*>(delegate_)->GetAppPath();
    command_line->AppendSwitchPath(switches::kAppPath, app_path);
  }
  content::WebContents* web_contents = GetWebContentsFromProcessID(process_id);
  if (web_contents) {
    
    
    
    
    
    
    if (web_contents->GetVisibleURL().SchemeIs("chrome-devtools")) {
      command_line->AppendSwitch(service_manager::switches::kNoSandbox);
      command_line->AppendSwitch(::switches::kNoZygote);
    }
    auto* web_preferences = WebContentsPreferences::From(web_contents);
    if (web_preferences)
      web_preferences->AppendCommandLineSwitches(command_line);
    SessionPreferences::AppendExtraCommandLineSwitches(
        web_contents->GetBrowserContext(), command_line);
  }
}
void AtomBrowserClient::DidCreatePpapiPlugin(content::BrowserPpapiHost* host) {