Add logging for SettingsPanels

The 3 main categories are:
- Panel Opened
- Panel Closed
- Panel Slice interaction

There are 3 close events:
- See more button
- Done button
- Clicking outside the panel

Slice interactions will log the Uri of the Slice and the ActionType,
such as Toggle, Slider, Content (intent).

Change-Id: Iecad948f39f50dd12ae1bcb23a5d523e0df8bb98
Fixes: 117804231
Test: robotests

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

@@ -19,6 +19,7 @@ package com.android.settings.panel;
 import static com.android.settings.media.MediaOutputSlice.MEDIA_PACKAGE_NAME;
 import static com.android.settings.slices.CustomSliceRegistry.MEDIA_OUTPUT_SLICE_URI;
 
+import android.app.settings.SettingsEnums;
 import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
@@ -71,4 +72,9 @@ public class MediaOutputPanel implements PanelContent {
     public Intent getSeeMoreIntent() {
         return null;
     }
+
+    @Override
+    public int getMetricsCategory() {
+        return SettingsEnums.PANEL_MEDIA_OUTPUT;
+    }
 }