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### Issue Details

* **Electron Version:**
  * Tested with 8.0.0 and v9.0.0-beta.1
* **Operating System:**
  * macOS 10.15.3 (19D76)
* **Last Known Working Electron version:**
  * 7.1.12

### Expected Behavior

`navigator.mediaDevices.enumerateDevices()` should return a list of MediaDevices with a `label` and a `deviceId` property. The `deviceId` property should stay the same across reloads and restarts.

### Actual Behavior
The `deviceId` property changes with every reload/restart.

### To Reproduce
Simply execute `navigator.mediaDevices.enumerateDevices()` in the renderer process and compare the ids of the media devices to a different execution.

See this fork for an example:
https://github.com/codedrift/electron-quick-start

```sh
$ git clone https://github.com/codedrift/electron-quick-start -b media-device-ids
$ npm install
$ npm start || electron .
```

### Additional Information
It seems to work fine in a regular Chrome 80 browser. 

shell/browser/electron_browser_client.cc
#include "shell/browser/electron_browser_context.h"
#include "shell/browser/electron_browser_main_parts.h"
#include "shell/browser/electron_navigation_throttle.h"
#include "shell/browser/electron_paths.h"
#include "shell/browser/electron_quota_permission_context.h"
#include "shell/browser/electron_speech_recognition_manager_delegate.h"
#include "shell/browser/font_defaults.h"
#include "shell/browser/media/media_capture_devices_dispatcher.h"
#include "shell/browser/native_window.h"
#include "shell/browser/net/network_context_service.h"
#include "shell/browser/net/network_context_service_factory.h"
#include "shell/browser/net/proxying_url_loader_factory.h"
#include "shell/browser/net/proxying_websocket.h"
#include "shell/browser/net/system_network_context_manager.h"
#include "shell/browser/network_hints_handler_impl.h"
#include "shell/browser/notifications/notification_presenter.h"
#include "shell/browser/notifications/platform_notification_service.h"
#include "shell/browser/session_preferences.h"
#include "shell/browser/ui/devtools_manager_delegate.h"
#include "shell/browser/web_contents_permission_helper.h"
#include "shell/browser/web_contents_preferences.h"
#include "shell/browser/window_list.h"
#include "shell/common/api/api.mojom.h"
#include "shell/common/application_info.h"
#include "shell/common/options_switches.h"
#include "shell/common/platform_util.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/native_theme/native_theme.h"
#include "v8/include/v8.h"
#if defined(OS_WIN)