Changes to icon picker for reusability in "add mode" flow

* Don't finish the fragment from the controller (ugh!) instead just report the selected icon via a listener.
* Highlight the selected icon in the list.
* Cache the icon drawables (since we're using selectors for the colors, we don't need to swap them, one per icon resource id is enough).
* Improved the tests a bit too.

Bug: 333901673
Bug: 326442408
Test: ates
Flag: android.app.modes_ui
Change-Id: Ib2ec7a7e3ed99b13f9264aa6f7c209ee3f6967a0

src/com/android/settings/notification/modes/ZenModeFragment.java

@@ -18,13 +18,14 @@ package com.android.settings.notification.modes;
 
 import android.app.AlertDialog;
 import android.app.Application;
-import android.app.AutomaticZenRule;
 import android.app.settings.SettingsEnums;
 import android.content.Context;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 
+import androidx.annotation.NonNull;
+
 import com.android.settings.R;
 import com.android.settingslib.applications.ApplicationsState;
 import com.android.settingslib.core.AbstractPreferenceController;
@@ -72,11 +73,9 @@ public class ZenModeFragment extends ZenModeFragmentBase {
 
         // Set title for the entire screen
         ZenMode mode = getMode();
-        AutomaticZenRule azr = getAZR();
-        if (mode == null || azr == null) {
-            return;
+        if (mode != null) {
+            requireActivity().setTitle(mode.getName());
         }
-        getActivity().setTitle(azr.getName());
     }
 
     @Override
@@ -92,7 +91,7 @@ public class ZenModeFragment extends ZenModeFragmentBase {
     }
 
     @Override
-    protected boolean onOptionsItemSelected(MenuItem item, ZenMode zenMode) {
+    protected boolean onOptionsItemSelected(MenuItem item, @NonNull ZenMode zenMode) {
         switch (item.getItemId()) {
             case DELETE_MODE:
                 new AlertDialog.Builder(mContext)