-> Enabled partial updates to app widgets through AppWidgetManager.

Partial updates are not cached by the AppWidgetService.
-> Added the ability to insert commands with no parameters into
   RemoteViews objects.
-> Added showNext() and showPrevious() methods to RemoteViews.
-> Made showNext() / showPrevious() of AdapterViewFlipper remotable.

Change-Id: Ic5491bb374424a54728c4ca92b94b1f00dfb87ff

services/java/com/android/server/AppWidgetService.java

@@ -425,6 +425,23 @@ class AppWidgetService extends IAppWidgetService.Stub
         }
     }
 
+    public void partiallyUpdateAppWidgetIds(int[] appWidgetIds, RemoteViews views) {
+        if (appWidgetIds == null) {
+            return;
+        }
+        if (appWidgetIds.length == 0) {
+            return;
+        }
+        final int N = appWidgetIds.length;
+
+        synchronized (mAppWidgetIds) {
+            for (int i=0; i<N; i++) {
+                AppWidgetId id = lookupAppWidgetIdLocked(appWidgetIds[i]);
+                updateAppWidgetInstanceLocked(id, views, true);
+            }
+        }
+    }
+
     public void notifyAppWidgetViewDataChanged(int[] appWidgetIds, RemoteViews views, int viewId) {
         if (appWidgetIds == null) {
             return;
@@ -459,11 +476,17 @@ class AppWidgetService extends IAppWidgetService.Stub
     }
 
     void updateAppWidgetInstanceLocked(AppWidgetId id, RemoteViews views) {
+        updateAppWidgetInstanceLocked(id, views, false);
+    }
+
+    void updateAppWidgetInstanceLocked(AppWidgetId id, RemoteViews views, boolean isPartialUpdate) {
         // allow for stale appWidgetIds and other badness
         // lookup also checks that the calling process can access the appWidgetId
         // drop unbound appWidgetIds (shouldn't be possible under normal circumstances)
         if (id != null && id.provider != null && !id.provider.zombie && !id.host.zombie) {
-            id.views = views;
+
+            // We do not want to save this RemoteViews
+            if (!isPartialUpdate) id.views = views;
 
             // is anyone listening?
             if (id.host.callbacks != null) {