Remove now-unnecessary .obj() in Java method calls.

net/android/keystore.cc

Index: net/android/keystore.cc
diff --git a/net/android/keystore.cc b/net/android/keystore.cc
index f6488187563cd456c8a26f0d7b039335460458be..cb179008dc724ff8e3e76b72154b49b459a325b0 100644
--- a/net/android/keystore.cc
+++ b/net/android/keystore.cc
@@ -59,7 +59,7 @@ bool RawSignDigestWithPrivateKey(jobject private_key_ref,
   // Invoke platform API
   ScopedJavaLocalRef<jbyteArray> signature_ref =
       Java_AndroidKeyStore_rawSignDigestWithPrivateKey(env, private_key_ref,
-                                                       digest_ref.obj());
+                                                       digest_ref);
   if (HasException(env) || signature_ref.is_null())
     return false;