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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 "sandbox/win/src/sandbox_policy.h"
#endif
#if defined(USE_NSS_CERTS)
#include "net/ssl/client_cert_store_nss.h"
#elif defined(OS_WIN)
#include "net/ssl/client_cert_store_win.h"
#elif defined(OS_MACOSX)
#include "net/ssl/client_cert_store_mac.h"
#elif defined(USE_OPENSSL)
#include "net/ssl/client_cert_store.h"
#endif
#if BUILDFLAG(ENABLE_BUILTIN_SPELLCHECKER)
#include "chrome/browser/spellchecker/spell_check_host_chrome_impl.h"  
#include "components/spellcheck/common/spellcheck.mojom.h"  
#endif
#if BUILDFLAG(ENABLE_PEPPER_FLASH)
#include "chrome/browser/renderer_host/pepper/chrome_browser_pepper_host_factory.h"
#endif  
#if BUILDFLAG(OVERRIDE_LOCATION_PROVIDER)
#include "shell/browser/fake_location_provider.h"
#endif  
#if BUILDFLAG(ENABLE_TTS)
#include "chrome/browser/speech/tts_controller_delegate_impl.h"
#endif  
#if BUILDFLAG(ENABLE_PRINTING)
#include "chrome/browser/printing/printing_message_filter.h"
#endif  
#if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
#include "chrome/common/webui_url_constants.h"
#include "content/public/browser/child_process_security_policy.h"