* 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
#include "atom/browser/atom_browser_context.h"
#include "atom/browser/atom_browser_main_parts.h"
#include "atom/browser/atom_navigation_throttle.h"
#include "atom/browser/atom_quota_permission_context.h"
#include "atom/browser/atom_resource_dispatcher_host_delegate.h"
#include "atom/browser/atom_speech_recognition_manager_delegate.h"
#include "atom/browser/child_web_contents_tracker.h"
#include "atom/browser/font_defaults.h"
#include "atom/browser/io_thread.h"
#include "atom/browser/media/media_capture_devices_dispatcher.h"
#include "atom/browser/native_window.h"
#include "atom/browser/notifications/notification_presenter.h"
#include "atom/browser/notifications/platform_notification_service.h"
#include "atom/browser/session_preferences.h"
#include "atom/browser/ui/devtools_manager_delegate.h"
#include "atom/browser/web_contents_permission_helper.h"
#include "atom/browser/web_contents_preferences.h"
#include "atom/browser/window_list.h"
#include "atom/common/options_switches.h"
#include "atom/common/platform_util.h"
#include "base/command_line.h"
#include "base/environment.h"
#include "base/files/file_util.h"
#include "base/json/json_reader.h"
#include "base/lazy_instance.h"
#include "base/no_destructor.h"
#include "base/path_service.h"
#include "base/stl_util.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"