App Bubble control page should always be available, even if off globally

There is API to open up the app-specific bubble page, therefor, we should
always show the toggle. The previous work to move bubbles to developer
settings broke this.

This CL adds a param to the controller to note whether it's the app
specific page or not (since controller is also used for channel settings)
to enable this behaviour.

Added a test for this situation.

Test: make -j40 RunSettingsRoboTests ROBOTEST_FILTER=Bubble
Bug: 131846917
Change-Id: I72b1f4b5b033d1b24281061cfa6bed4d734dfcb1

src/com/android/settings/notification/BubblePreferenceController.java

@@ -41,11 +41,13 @@ public class BubblePreferenceController extends NotificationPreferenceController
     static final int SYSTEM_WIDE_OFF = 0;
 
     private FragmentManager mFragmentManager;
+    private boolean mIsAppPage;
 
     public BubblePreferenceController(Context context, @Nullable FragmentManager fragmentManager,
-            NotificationBackend backend) {
+            NotificationBackend backend, boolean isAppPage) {
         super(context, backend);
         mFragmentManager = fragmentManager;
+        mIsAppPage = isAppPage;
     }
 
     @Override
@@ -58,7 +60,7 @@ public class BubblePreferenceController extends NotificationPreferenceController
         if (!super.isAvailable()) {
             return false;
         }
-        if (!isGloballyEnabled()) {
+        if (!mIsAppPage && !isGloballyEnabled()) {
             return false;
         }
         if (mChannel != null) {