Restrict access to instant app data in usage stats

- Events are obfuscated based on whether the app was instant or not at
the time each event was logged.

- UsageStats are obfuscated based on whether each app is instant or
not at the moment.

Bug 38202133
Test: Manual test using UsageStatsTest and instant apps

Change-Id: I3c74309196b88d010d317cb0dd6749bf4624e876
diff --git a/core/java/android/content/pm/PackageManagerInternal.java b/core/java/android/content/pm/PackageManagerInternal.java
index 426f3cf..87e6a84 100644
--- a/core/java/android/content/pm/PackageManagerInternal.java
+++ b/core/java/android/content/pm/PackageManagerInternal.java
@@ -341,4 +341,7 @@
      * Return the taget SDK version for the app with the given UID.
      */
     public abstract int getUidTargetSdkVersion(int uid);
+
+    /** Whether the binder caller can access instant apps. */
+    public abstract boolean canAccessInstantApps(int callingUid);
 }