API tweaks

* Make the PhoneAccountSuggestion ctor public
* Change protection level of the bind-suggestion-service permission to
signature-only.

Fixes: 126442573
Fixes: 126442403
Test: CTS
Change-Id: Ic6d44989efd28420a5e9e7e9c365318538d140bb
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index e40d97b..35bc46a 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -1839,12 +1839,12 @@
 
     <!-- Must be required by a {@link android.telecom.PhoneAccountSuggestionService},
          to ensure that only the system can bind to it.
-         <p>Protection level: signature|privileged
+         <p>Protection level: signature
          @SystemApi
          @hide
     -->
     <permission android:name="android.permission.BIND_PHONE_ACCOUNT_SUGGESTION_SERVICE"
-        android:protectionLevel="signature|privileged" />
+        android:protectionLevel="signature" />
 
     <!-- Must be required by a {@link android.telecom.CallRedirectionService},
          to ensure that only the system can bind to it.