Add unaudited exported flag to exposed runtime receivers

Android T allows apps to declare a runtime receiver as not exported
by invoking registerReceiver with a new RECEIVER_NOT_EXPORTED flag;
receivers registered with this flag will only receive broadcasts from
the platform and the app itself. However to ensure developers can
properly protect their receivers, all apps targeting T or later
registering a receiver for non-system broadcasts must specify either
the exported or not exported flag when invoking #registerReceiver;
if one of these flags is not provided, the platform will throw a
SecurityException. This commit updates all the exposed receivers
with a new RECEIVER_EXPORTED_UNAUDITED flag to maintain the existing
behavior of exporting the receiver while also flagging the receiver
for audit before the T release.

Bug: 161145287
Test: Build
Change-Id: I165dbff34a03180a770d7cd621464f3d832b8095

packages/PackageInstaller/src/com/android/packageinstaller/wear/PackageInstallerImpl.java

@@ -264,7 +264,8 @@ public class PackageInstallerImpl {
         String action = ACTION_INSTALL_COMMIT + "." + packageName;
         IntentFilter intentFilter = new IntentFilter();
         intentFilter.addAction(action);
-        mContext.registerReceiver(broadcastReceiver, intentFilter);
+        mContext.registerReceiver(broadcastReceiver, intentFilter,
+                Context.RECEIVER_EXPORTED_UNAUDITED);
 
         // Create a matching PendingIntent and use it to generate the IntentSender
         Intent broadcastIntent = new Intent(action);