Fix history task stack

Test: manual
Bug: 154721261
Change-Id: Ib39fff447d0d6571b4267700eaf39e425fa114d7
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 11c67a1..3bb9f5d 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -1200,8 +1200,7 @@
 
         <activity
             android:name=".notification.history.NotificationHistoryActivity"
-            android:label="@string/notification_history_title"
-            android:taskAffinity="com.android.settings.notification">
+            android:label="@string/notification_history_title">
             <intent-filter android:priority="1">
                 <action android:name="android.settings.NOTIFICATION_HISTORY" />
                 <category android:name="android.intent.category.DEFAULT" />
@@ -2532,7 +2531,6 @@
         <activity
             android:name="Settings$ConfigureNotificationSettingsActivity"
             android:label="@string/configure_notification_settings"
-            android:taskAffinity="com.android.settings.notification"
             android:exported="true">
             <intent-filter android:priority="1">
                 <action android:name="android.settings.NOTIFICATION_SETTINGS" />
diff --git a/src/com/android/settings/notification/history/NotificationHistoryActivity.java b/src/com/android/settings/notification/history/NotificationHistoryActivity.java
index 005b4bb..c45242e 100644
--- a/src/com/android/settings/notification/history/NotificationHistoryActivity.java
+++ b/src/com/android/settings/notification/history/NotificationHistoryActivity.java
@@ -200,20 +200,6 @@
         super.onDestroy();
     }
 
-    @Override
-    public void onBackPressed() {
-        handleBackPressed();
-    }
-
-    private void handleBackPressed() {
-        if (getFragmentManager().getBackStackEntryCount() > 1) {
-            super.onBackPressed();
-        } else {
-            startActivity(new Intent(Settings.ACTION_NOTIFICATION_SETTINGS));
-            finish();
-        }
-    }
-
     private void bindSwitch() {
         if (mSwitchBar != null) {
             mSwitchBar.setSwitchBarText(R.string.notification_history_toggle,