Delete the outdated list widget demo code.

- "rv" is not recommended and "glance" is the preferred widget framework.
- Sizing on those widgets is off. The new canonical layout contain example of lists and are recommended.

Author: shamalip

samples/user-interface/appwidgets/src/main/AndroidManifest.xml

@@ -30,15 +30,6 @@
             android:name="com.example.platform.ui.appwidgets.AppWidgetPinnedReceiver"
             android:exported="false" />
 
-        <activity
-            android:theme="@style/Theme.AppWidget"
-            android:name=".rv.list.ListWidgetConfigureActivity"
-            android:exported="false">
-            <intent-filter>
-                <action android:name="android.appwidget.action.APPWIDGET_CONFIGURE" />
-            </intent-filter>
-        </activity>
-
         <!-- Toolbar variants -->
 
         <!-- Toolbar with header -->
@@ -162,28 +153,6 @@
                 android:resource="@xml/sample_image_grid_widget_info" />
         </receiver>
 
-        <receiver
-            android:name=".rv.list.ListAppWidget"
-            android:exported="false">
-            <intent-filter>
-                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
-            </intent-filter>
-
-            <meta-data
-                android:name="android.appwidget.provider"
-                android:resource="@xml/app_widget_list_rv" />
-        </receiver>
-        <receiver
-            android:name=".rv.buttons.ButtonsAppWidget"
-            android:exported="false">
-            <intent-filter>
-                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
-            </intent-filter>
-
-            <meta-data
-                android:name="android.appwidget.provider"
-                android:resource="@xml/app_widget_buttons_rv" />
-        </receiver>
         <receiver
             android:name=".rv.weather.WeatherForecastAppWidget"
             android:enabled="@bool/weather_appwidget_enabled"
@@ -196,18 +165,6 @@
                 android:name="android.appwidget.provider"
                 android:resource="@xml/app_widget_weather_forecast" />
         </receiver>
-        <receiver
-            android:name=".glance.list.ListGlanceWidgetReceiver"
-            android:enabled="@bool/glance_appwidget_available"
-            android:exported="false">
-            <intent-filter>
-                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
-            </intent-filter>
-
-            <meta-data
-                android:name="android.appwidget.provider"
-                android:resource="@xml/app_widget_list_glance" />
-        </receiver>
         <receiver
             android:name=".glance.weather.WeatherGlanceWidgetReceiver"
             android:label="@string/glance_weather"