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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 "content/public/browser/render_process_host.h"
#include "content/public/browser/render_view_host.h"
#include "content/public/browser/site_instance.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 "extensions/browser/extension_navigation_ui_data.h"
#include "extensions/browser/extension_protocols.h"
#include "extensions/common/constants.h"
#include "net/base/escape.h"
#include "net/ssl/ssl_cert_request_info.h"
#include "ppapi/buildflags/buildflags.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/features.h"
#include "services/network/public/cpp/resource_request_body.h"
#include "services/service_manager/public/cpp/binder_map.h"
#include "shell/app/manifests.h"
#include "shell/browser/api/electron_api_app.h"
#include "shell/browser/api/electron_api_protocol.h"
#include "shell/browser/api/electron_api_session.h"
#include "shell/browser/api/electron_api_web_contents.h"
#include "shell/browser/api/electron_api_web_request.h"
#include "shell/browser/child_web_contents_tracker.h"
#include "shell/browser/electron_autofill_driver_factory.h"