Add function to AppWidgetService for updating widget visibility

Currently, when the widget host stops listening to the widget updates,
the callback will be set to null and the updates to the widget will be
stashed on the service side. Additionally, the visibility of the widget
will be changed. For an upcoming change to the launcher side, a function
that only changes the visibility should be added.

Test: N/A
Bug: 235358918
Change-Id: I9a0f244ca76b378d9c337e0a364bca5955f5ae96

core/java/android/appwidget/AppWidgetHost.java

@@ -328,6 +328,22 @@ public class AppWidgetHost {
         }
     }
 
+    /**
+     * Set the visibiity of all widgets associated with this host to hidden
+     *
+     * @hide
+     */
+    public void setAppWidgetHidden() {
+        if (sService == null) {
+            return;
+        }
+        try {
+            sService.setAppWidgetHidden(mContextOpPackageName, mHostId);
+        } catch (RemoteException e) {
+            throw new RuntimeException("System server dead?", e);
+        }
+    }
+
     /**
      * Set the host's interaction handler.
      *

core/java/com/android/internal/appwidget/IAppWidgetService.aidl

@@ -45,6 +45,7 @@ interface IAppWidgetService {
     @UnsupportedAppUsage(maxTargetSdk = 30, trackingBug = 170729553)
     RemoteViews getAppWidgetViews(String callingPackage, int appWidgetId);
     int[] getAppWidgetIdsForHost(String callingPackage, int hostId);
+    void setAppWidgetHidden(in String callingPackage, int hostId);
     IntentSender createAppWidgetConfigIntentSender(String callingPackage, int appWidgetId,
             int intentFlags);
 

services/appwidget/java/com/android/server/appwidget/AppWidgetServiceImpl.java

@@ -865,6 +865,33 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
         }
     }
 
+    @Override
+    public void setAppWidgetHidden(String callingPackage, int hostId) {
+        final int userId = UserHandle.getCallingUserId();
+
+        if (DEBUG) {
+            Slog.i(TAG, "setAppWidgetHidden() " + userId);
+        }
+
+        mSecurityPolicy.enforceCallFromPackage(callingPackage);
+
+        synchronized (mLock) {
+            ensureGroupStateLoadedLocked(userId, /* enforceUserUnlockingOrUnlocked */false);
+
+            HostId id = new HostId(Binder.getCallingUid(), hostId, callingPackage);
+            Host host = lookupHostLocked(id);
+
+            if (host != null) {
+                try {
+                    mAppOpsManagerInternal.updateAppWidgetVisibility(host.getWidgetUids(), false);
+                } catch (NullPointerException e) {
+                    Slog.e(TAG, "setAppWidgetHidden(): Getting host uids: " + host.toString(), e);
+                    throw e;
+                }
+            }
+        }
+    }
+
     @Override
     public void deleteAppWidgetId(String callingPackage, int appWidgetId) {
         final int userId = UserHandle.getCallingUserId();