Enable package verification

Turn on package verification, if a verifier exists. Play app is a verifier.

Bug: 7064853
Change-Id: Id7d478a216d10b0a612678d6a9b0ee7f2037204a

Author: rich cannings

services/java/com/android/server/pm/PackageManagerService.java

@@ -215,7 +215,7 @@ public class PackageManagerService extends IPackageManager.Stub {
     /**
      * Whether verification is enabled by default.
      */
-    private static final boolean DEFAULT_VERIFY_ENABLE = false;
+    private static final boolean DEFAULT_VERIFY_ENABLE = true;
 
     /**
      * The default maximum time to wait for the verification agent to return in