Adds initial key systems support for Chromecast.

chromecast/shell/renderer/key_systems_cast_simple.cc

 // Copyright 2014 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 "chromecast/android/platform_jni_loader.h"
+#include "chromecast/shell/renderer/key_systems_cast.h"
 
 namespace chromecast {
-namespace android {
+namespace shell {
 
-bool PlatformRegisterJni(JNIEnv* env) {
+void AddChromecastPlatformKeySystems(
+    std::vector<content::KeySystemInfo>* key_systems_info) {
   // Intentional no-op for public build.
-  return true;
 }
 
-}  // namespace android
+}  // namespace shell
 }  // namespace chromecast