Fix code style and gyp files in cast to build cast_unittest

media/cast/pacing/mock_paced_packet_sender.cc

 // Copyright 2013 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.
 
-#include "media/base/media_keys.h"
+#include "media/cast/pacing/mock_paced_packet_sender.h"
 
 namespace media {
+namespace cast {
 
-MediaKeys::MediaKeys() {}
+MockPacedPacketSender::MockPacedPacketSender() {
+}
 
-MediaKeys::~MediaKeys() {}
+MockPacedPacketSender::~MockPacedPacketSender() {
+}
 
-Decryptor* MediaKeys::GetDecryptor() { return NULL; }
-
+}  // namespace cast
 }  // namespace media