Add additional overriding methods to signature files

This change adds overriding methods that are essential to compile the
stubs generated from the signature files.

More information and the background for this change is available at
go/add-overriding-one-pager.

Test: m checkapi
Change-Id: Ifc1876eb60a4b716f72c86003dc9bea0081e9a4c
diff --git a/test-mock/api/removed.txt b/test-mock/api/removed.txt
index fa2fbd2..0c800b6 100644
--- a/test-mock/api/removed.txt
+++ b/test-mock/api/removed.txt
@@ -1,6 +1,4 @@
 // Signature format: 2.0
-// - add-additional-overrides=no
-// - migrating=Migration in progress see b/299366704
 package android.test.mock {
 
   public class MockContext extends android.content.Context {
@@ -11,7 +9,7 @@
   @Deprecated public class MockPackageManager extends android.content.pm.PackageManager {
     method @Deprecated public String getDefaultBrowserPackageName(int);
     method @Deprecated public boolean setDefaultBrowserPackageName(String, int);
-    method public boolean setInstantAppCookie(@NonNull byte[]);
+    method @Deprecated public boolean setInstantAppCookie(@NonNull byte[]);
   }
 
 }