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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
program != plugin_child_path) {
      child_path = content::ChildProcessHost::GetChildPath(
          content::ChildProcessHost::CHILD_NORMAL);
      CHECK_EQ(program, child_path)
          << "Aborted from launching unexpected helper executable";
    }
#else
    base::PathService::Get(content::CHILD_PROCESS_EXE, &child_path);
    CHECK_EQ(program, child_path);
#endif
  }
  std::string process_type =
      command_line->GetSwitchValueASCII(::switches::kProcessType);
  if (process_type == ::switches::kUtilityProcess ||
      process_type == ::switches::kRendererProcess) {
    
    static const char* const kCommonSwitchNames[] = {
        switches::kStandardSchemes,      switches::kEnableSandbox,
        switches::kSecureSchemes,        switches::kBypassCSPSchemes,
        switches::kCORSSchemes,          switches::kFetchSchemes,
        switches::kServiceWorkerSchemes, switches::kEnableApiFilteringLogging};
    command_line->CopySwitchesFrom(*base::CommandLine::ForCurrentProcess(),
                                   kCommonSwitchNames,
                                   base::size(kCommonSwitchNames));
  }
  if (process_type == ::switches::kRendererProcess) {
#if defined(OS_WIN)
    
    PWSTR current_app_id;
    if (SUCCEEDED(GetCurrentProcessExplicitAppUserModelID(&current_app_id))) {