Remove reflection now we are building against L

Remove reflection and update changed renamed L APIs
now that branch has L sdk.

Change-Id: I223c6528487110eb328e2e229bbcbefb701e0c20
diff --git a/src/com/android/launcher3/LauncherAppState.java b/src/com/android/launcher3/LauncherAppState.java
index 79bc084..27bcd81 100644
--- a/src/com/android/launcher3/LauncherAppState.java
+++ b/src/com/android/launcher3/LauncherAppState.java
@@ -95,7 +95,7 @@
         mBuildInfo = BuildInfo.loadByName(sContext.getString(R.string.build_info_class));
         mModel = new LauncherModel(this, mIconCache, mAppFilter);
         final LauncherAppsCompat launcherApps = LauncherAppsCompat.getInstance(sContext);
-        launcherApps.addOnAppsChangedListener(mModel);
+        launcherApps.addOnAppsChangedCallback(mModel);
 
         // Register intent receivers
         IntentFilter filter = new IntentFilter();
@@ -128,7 +128,7 @@
     public void onTerminate() {
         sContext.unregisterReceiver(mModel);
         final LauncherAppsCompat launcherApps = LauncherAppsCompat.getInstance(sContext);
-        launcherApps.removeOnAppsChangedListener(mModel);
+        launcherApps.removeOnAppsChangedCallback(mModel);
 
         ContentResolver resolver = sContext.getContentResolver();
         resolver.unregisterContentObserver(mFavoritesObserver);