* 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 "base/strings/utf_string_conversions.h"
#include "base/task/post_task.h"
#include "chrome/browser/browser_process.h"
#include "components/net_log/chrome_net_log.h"
#include "content/public/browser/browser_ppapi_host.h"
#include "content/public/browser/browser_task_traits.h"
#include "content/public/browser/client_certificate_delegate.h"
#include "content/public/browser/render_frame_host.h"
#include "content/public/browser/render_process_host.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/browser/resource_dispatcher_host.h"
#include "content/public/browser/site_instance.h"
#include "content/public/browser/web_contents.h"
#include "content/public/common/content_paths.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/service_names.mojom.h"
#include "content/public/common/url_constants.h"
#include "content/public/common/web_preferences.h"
#include "electron/buildflags/buildflags.h"
#include "electron/grit/electron_resources.h"
#include "net/base/escape.h"
#include "net/ssl/ssl_cert_request_info.h"
#include "ppapi/host/ppapi_host.h"
#include "printing/buildflags/buildflags.h"
#include "services/device/public/cpp/geolocation/location_provider.h"
#include "services/network/public/cpp/resource_request_body.h"
#include "services/proxy_resolver/public/mojom/proxy_resolver.mojom.h"
#include "services/service_manager/sandbox/switches.h"
#include "ui/base/l10n/l10n_util.h"
#include "ui/base/resource/resource_bundle.h"