Replaced raw string arguments for Context.getSystemService() with final Context variables

Change-Id: If5139a1526101292e5da557bfad3f4db80fb64a8

Author: firefart

core/java/android/app/Dialog.java

@@ -136,7 +136,7 @@ public Dialog(Context context) {
     public Dialog(Context context, int theme) {
         mContext = new ContextThemeWrapper(
             context, theme == 0 ? com.android.internal.R.style.Theme_Dialog : theme);
-        mWindowManager = (WindowManager)context.getSystemService("window");
+        mWindowManager = (WindowManager)context.getSystemService(Context.WINDOW_SERVICE);
         Window w = PolicyManager.makeNewWindow(mContext);
         mWindow = w;
         w.setCallback(this);

core/java/android/widget/MediaController.java

@@ -123,7 +123,7 @@ public MediaController(Context context) {
     }
 
     private void initFloatingWindow() {
-        mWindowManager = (WindowManager)mContext.getSystemService("window");
+        mWindowManager = (WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE);
         mWindow = PolicyManager.makeNewWindow(mContext);
         mWindow.setWindowManager(mWindowManager, null, null);
         mWindow.requestFeature(Window.FEATURE_NO_TITLE);

tests/StatusBar/src/com/android/statusbartest/NotificationTestList.java

@@ -21,6 +21,7 @@
 import android.widget.ArrayAdapter;
 import android.view.View;
 import android.widget.ListView;
+import android.content.Context;
 import android.content.ContentResolver;
 import android.content.Intent;
 import android.app.Notification;
@@ -60,7 +61,7 @@ protected Test[] tests() {
     private Test[] mTests = new Test[] {
         new Test("Off and sound") {
             public void run() {
-                PowerManager pm = (PowerManager)NotificationTestList.this.getSystemService("power");
+                PowerManager pm = (PowerManager)NotificationTestList.this.getSystemService(Context.POWER_SERVICE);
                 PowerManager.WakeLock wl = 
                             pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "sound");
                 wl.acquire();
@@ -549,7 +550,7 @@ public void run() {
             public void run()
             {
                 PowerManager.WakeLock wl
-                        = ((PowerManager)NotificationTestList.this.getSystemService("power"))
+                        = ((PowerManager)NotificationTestList.this.getSystemService(Context.POWER_SERVICE))
                             .newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "crasher");
                 wl.acquire();
                 mHandler.postDelayed(new Runnable() {