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/app/usage/UsageEvents.java b/core/java/android/app/usage/UsageEvents.java
index ce8b05a..0d7a941 100644
--- a/core/java/android/app/usage/UsageEvents.java
+++ b/core/java/android/app/usage/UsageEvents.java
@@ -15,10 +15,13 @@
  */
 package android.app.usage;
 
+import android.annotation.IntDef;
 import android.content.res.Configuration;
 import android.os.Parcel;
 import android.os.Parcelable;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 import java.util.Arrays;
 import java.util.List;
 
@@ -28,6 +31,12 @@
  */
 public final class UsageEvents implements Parcelable {
 
+    /** @hide */
+    public static final String INSTANT_APP_PACKAGE_NAME = "android.instant_app";
+
+    /** @hide */
+    public static final String INSTANT_APP_CLASS_NAME = "android.instant_class";
+
     /**
      * An event representing a state change for a component.
      */
@@ -91,6 +100,17 @@
          */
         public static final int CHOOSER_ACTION = 9;
 
+        /** @hide */
+        public static final int FLAG_IS_PACKAGE_INSTANT_APP = 1 << 0;
+
+        /** @hide */
+        @IntDef(flag = true,
+                value = {
+                        FLAG_IS_PACKAGE_INSTANT_APP,
+                })
+        @Retention(RetentionPolicy.SOURCE)
+        public @interface EventFlags {}
+
         /**
          * {@hide}
          */
@@ -145,6 +165,27 @@
          */
         public String[] mContentAnnotations;
 
+        /** @hide */
+        @EventFlags
+        public int mFlags;
+
+        public Event() {
+        }
+
+        /** @hide */
+        public Event(Event orig) {
+            mPackage = orig.mPackage;
+            mClass = orig.mClass;
+            mTimeStamp = orig.mTimeStamp;
+            mEventType = orig.mEventType;
+            mConfiguration = orig.mConfiguration;
+            mShortcutId = orig.mShortcutId;
+            mAction = orig.mAction;
+            mContentType = orig.mContentType;
+            mContentAnnotations = orig.mContentAnnotations;
+            mFlags = orig.mFlags;
+        }
+
         /**
          * The package name of the source of this event.
          */
@@ -196,6 +237,20 @@
         public String getShortcutId() {
             return mShortcutId;
         }
+
+        /** @hide */
+        public Event getObfuscatedIfInstantApp() {
+            if ((mFlags & FLAG_IS_PACKAGE_INSTANT_APP) == 0) {
+                return this;
+            }
+            final Event ret = new Event(this);
+            ret.mPackage = INSTANT_APP_PACKAGE_NAME;
+            ret.mClass = INSTANT_APP_CLASS_NAME;
+
+            // Note there are other string fields too, but they're for app shortcuts and choosers,
+            // which instant apps can't use anyway, so there's no need to hide them.
+            return ret;
+        }
     }
 
     // Only used when creating the resulting events. Not used for reading/unparceling.
diff --git a/core/java/android/app/usage/UsageStats.java b/core/java/android/app/usage/UsageStats.java
index 0874095..7eef85c 100644
--- a/core/java/android/app/usage/UsageStats.java
+++ b/core/java/android/app/usage/UsageStats.java
@@ -85,6 +85,17 @@
         mChooserCounts = stats.mChooserCounts;
     }
 
+    /**
+     * {@hide}
+     */
+    public UsageStats getObfuscatedForInstantApp() {
+        final UsageStats ret = new UsageStats(this);
+
+        ret.mPackageName = UsageEvents.INSTANT_APP_PACKAGE_NAME;
+
+        return ret;
+    }
+
     public String getPackageName() {
         return mPackageName;
     }
diff --git a/core/java/android/app/usage/UsageStatsManagerInternal.java b/core/java/android/app/usage/UsageStatsManagerInternal.java
index 08595dd..dbaace2 100644
--- a/core/java/android/app/usage/UsageStatsManagerInternal.java
+++ b/core/java/android/app/usage/UsageStatsManagerInternal.java
@@ -127,7 +127,12 @@
 
     public abstract void applyRestoredPayload(int user, String key, byte[] payload);
 
-    /* Cache Quota Service API */
+    /**
+     * Return usage stats.
+     *
+     * @param obfuscateInstantApps whether instant app package names need to be obfuscated in the
+     *     result.
+     */
     public abstract List<UsageStats> queryUsageStatsForUser(
-            int userId, int interval, long beginTime, long endTime);
+            int userId, int interval, long beginTime, long endTime, boolean obfuscateInstantApps);
 }
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);
 }