[Mojo Video Capture] Cleanup naming of classes/files in services/video_capture

services/video_capture/public/interfaces/mock_video_capture_device.mojom

-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-module video_capture.mojom;
-
-// Instances are passed into MockVideoCaptureDevice::AllocateAndStart().
-// Even though this interface is empty, it is useful in testing in order to
-// have the MockVideoCaptureDevice take ownership of the MockDeviceClient
-// passed to it.
-interface MockDeviceClient {
-
-};
-
-// Essentially a Mojo equivalent of media::VideoCaptureDevice used for testing
-// that expected calls to this interface are made by the service implementation.
-// The Mojo equivalent is needed to allow such tests across the Mojo boundary.
-// This interface contains only simplified versions of the methods from
-// media::VideoCaptureDevice that we actually verify in tests.
-//
-// Similar to VideoCaptureDeviceProxy, this interface is an abstraction of a
-// device, but the purpose of the two interfaces is quite different.
-// VideoCaptureDeviceProxy is for production clients of the Mojo service to
-// interact with the devices. MockVideoCaptureDevice is for tests of the Mojo
-// service to allow verification of calls of the service made to instances of
-// media::VideoCaptureDevice.
-//
-// Instances can be added to the mock factory provided by the
-// VideoCaptureService.
-interface MockVideoCaptureDevice {
-  AllocateAndStart(MockDeviceClient client);
-  StopAndDeAllocate();
-};