Add entry point at output switcher to do group operation

-Entry point is available only when there are more than 1 connected device
-Add group Slice item when it is available
-Add intent filter in manifest
-Add test case

Bug: 146813761
Test: make -j42 RunSettingsRoboTests
Change-Id: If398b7a31219fd1910503d96fe7593622528c792

src/com/android/settings/panel/PanelFeatureProviderImpl.java

@@ -17,6 +17,7 @@
 package com.android.settings.panel;
 
 import static com.android.settingslib.media.MediaOutputSliceConstants.ACTION_MEDIA_OUTPUT;
+import static com.android.settingslib.media.MediaOutputSliceConstants.ACTION_MEDIA_OUTPUT_GROUP;
 
 import android.content.Context;
 import android.os.Bundle;
@@ -46,6 +47,8 @@ public class PanelFeatureProviderImpl implements PanelFeatureProvider {
                 return WifiPanel.create(context);
             case Settings.Panel.ACTION_VOLUME:
                 return VolumePanel.create(context);
+            case ACTION_MEDIA_OUTPUT_GROUP:
+                return MediaOutputGroupPanel.create(context, mediaPackageName);
         }
 
         throw new IllegalStateException("No matching panel for: "  + panelType);