Add "interactive" UI integration tests for PermissionRequestManager.

chrome/browser/media/webrtc/media_stream_devices_controller.h

Index: chrome/browser/media/webrtc/media_stream_devices_controller.h
diff --git a/chrome/browser/media/webrtc/media_stream_devices_controller.h b/chrome/browser/media/webrtc/media_stream_devices_controller.h
index 1777cd9b0e31fd1f9610b069259466169d75d41d..059ed42da9affc3096b32badc74c0940c6570ac0 100644
--- a/chrome/browser/media/webrtc/media_stream_devices_controller.h
+++ b/chrome/browser/media/webrtc/media_stream_devices_controller.h
@@ -28,6 +28,10 @@ namespace policy {
 class MediaStreamDevicesControllerBrowserTest;
 }
 
+namespace test {
+class MediaStreamDevicesControllerTestApi;
+}
+
 class MediaStreamDevicesController : public PermissionRequest {
  public:
   static void RequestPermissions(
@@ -67,6 +71,7 @@ class MediaStreamDevicesController : public PermissionRequest {
 
  private:
   friend class MediaStreamDevicesControllerTest;
+  friend class test::MediaStreamDevicesControllerTestApi;
   friend class policy::MediaStreamDevicesControllerBrowserTest;
 
   // Delegate showing permission prompts.