

### Preflight Checklist
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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/file_url_loader.h"
#include "content/public/browser/web_ui_url_loader_factory.h"
#include "extensions/browser/api/mime_handler_private/mime_handler_private.h"
#include "extensions/browser/extension_host.h"
#include "extensions/browser/extension_message_filter.h"
#include "extensions/browser/extension_navigation_throttle.h"
#include "extensions/browser/extension_registry.h"
#include "extensions/browser/guest_view/extensions_guest_view_message_filter.h"
#include "extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest.h"
#include "extensions/browser/info_map.h"
#include "extensions/browser/process_manager.h"
#include "extensions/browser/process_map.h"
#include "extensions/common/api/mime_handler.mojom.h"
#include "extensions/common/extension.h"
#include "shell/browser/extensions/electron_extension_system.h"
#include "shell/browser/extensions/electron_extension_web_contents_observer.h"
#endif
#if BUILDFLAG(ENABLE_PLUGINS)
#include "chrome/browser/plugins/plugin_response_interceptor_url_loader_throttle.h"  
#include "shell/browser/plugins/plugin_utils.h"
#endif
#if defined(OS_MACOSX)
#include "content/common/mac_helpers.h"
#include "content/public/common/child_process_host.h"
#endif
using content::BrowserThread;
namespace electron {
namespace {
bool g_suppress_renderer_process_restart = false;
bool IsSameWebSite(content::BrowserContext* browser_context,