Use AudioManager API instead of manually checking ringing volume.

This CL ensures that the Ringer class relies on the AudioManager#shouldNotificationSoundPlay API instead of manually checking ringing volume when determining if a ringtone should be played audibly for an MT call. This CL also adds the feature flag for all of the go/ring-my-car Telecom feature work.

Bug: 348707841
Flag: com.android.server.telecom.flags.ensure_in_car_ringing
Test: atest RingerTest

Change-Id: I7df60d54e4e6e8ede69e807a6091647104ea9863
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 90e4bd9..941bd5e 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -45,6 +45,8 @@
     <!-- Required to determine source of ongoing audio recordings. -->
     <uses-permission android:name="android.permission.MODIFY_AUDIO_ROUTING"/>
     <uses-permission android:name="android.permission.MODIFY_PHONE_STATE"/>
+    <!-- Required to query the audio framework to determine if a notification sound should play. -->
+    <uses-permission android:name="android.permission.QUERY_AUDIO_STATE"/>
     <uses-permission android:name="android.permission.READ_CALL_LOG"/>
     <!-- Required to check for direct to voicemail, to load custom ringtones for incoming calls
         which are specified on a per contact basis, and also to determine user preferred