Improve lifecycle of ZenModeFragment & friends

* Don't keep Settings observers longer than start-stop.
* Only call updateState() once on controllers during create->start->resume.
* Remove some duplicate controller update methods from ZenModesFragmentBase (we can directly call DashboardFragment's).
* Don't update controllers if unrelated modes were changed.
* Extract ZenSettingsObserver for use in the link tile later.
* Add tests.

Fixes: 353946788
Test: atest com.android.settings.notification.modes
Flag: android.app.modes_ui
Change-Id: I64b51714d699b5c3a592a76fcb615d2999998829

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

@@ -37,7 +37,6 @@ import androidx.annotation.NonNull;
 import androidx.annotation.StringRes;
 import androidx.annotation.VisibleForTesting;
 import androidx.preference.Preference;
-import androidx.preference.PreferenceScreen;
 
 import com.android.settings.R;
 import com.android.settingslib.PrimarySwitchPreference;
@@ -77,13 +76,6 @@ class ZenModeTriggerUpdatePreferenceController extends AbstractZenModePreference
         return !zenMode.isCustomManual() && !zenMode.isManualDnd();
     }
 
-    @Override
-    public void displayPreference(PreferenceScreen screen, @NonNull ZenMode zenMode) {
-        // Preload approved components, but only for the package that owns the rule (since it's the
-        // only package that can have a valid configurationActivity).
-        mServiceListing.loadApprovedComponents(zenMode.getRule().getPackageName());
-    }
-
     @Override
     void updateState(Preference preference, @NonNull ZenMode zenMode) {
         if (!isAvailable(zenMode)) {
@@ -137,6 +129,7 @@ class ZenModeTriggerUpdatePreferenceController extends AbstractZenModePreference
     @SuppressLint("SwitchIntDef")
     private void setUpForAppTrigger(Preference preference, ZenMode mode) {
         // App-owned mode may have triggerDescription, configurationActivity, or both/neither.
+        mServiceListing.loadApprovedComponents(mode.getRule().getPackageName());
         Intent configurationIntent =
                 mConfigurationActivityHelper.getConfigurationActivityIntentForMode(
                         mode, mServiceListing::findService);