Hide ephemerality

Change-Id: Ibf60366b3f00b1920e330cd804bcc1c550f8882a

Bug: 26404647
diff --git a/test-runner/src/android/test/mock/MockPackageManager.java b/test-runner/src/android/test/mock/MockPackageManager.java
index 01583f56..81aa6c6 100644
--- a/test-runner/src/android/test/mock/MockPackageManager.java
+++ b/test-runner/src/android/test/mock/MockPackageManager.java
@@ -322,21 +322,25 @@
         throw new UnsupportedOperationException();
     }
 
+    /** @hide */
     @Override
     public byte[] getEphemeralCookie() {
         return new byte[0];
     }
 
+    /** @hide */
     @Override
     public boolean isEphemeralApplication() {
         return false;
     }
 
+    /** @hide */
     @Override
     public int getEphemeralCookieMaxSizeBytes() {
         return 0;
     }
 
+    /** @hide */
     @Override
     public boolean setEphemeralCookie(@NonNull byte[] cookie) {
         return false;