Minor fixes to junit and robolectric BUILD.gn files.

third_party/robolectric/BUILD.gn

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/rules.gni")
 
 # GYP: //third_party/robolectric/robolectric.gyp:android-all-4.3_r2-robolectric-0
 java_prebuilt("android-all-4.3_r2-robolectric-0") {
-  visibility = [ ":*" ]
   jar_path = "lib/android-all-4.3_r2-robolectric-0.jar"
 }
 
 # GYP: //third_party/robolectric/robolectric.gyp:tagsoup-1.2
 java_prebuilt("tagsoup-1.2") {
-  visibility = [ ":*" ]
   jar_path = "lib/tagsoup-1.2.jar"
 }
 
 # GYP: //third_party/robolectric/robolectric.gyp:json-20080701
 java_prebuilt("json-20080701") {
-  visibility = [ ":*" ]
   jar_path = "lib/json-20080701.jar"
 }
 
 # GYP: //third_party/robolectric/robolectric.gyp:robolectric_jar
 java_prebuilt("robolectric_java") {
   testonly = true
   jar_path = "lib/robolectric-2.4-jar-with-dependencies.jar"
   deps = [
     ":android-all-4.3_r2-robolectric-0",
     ":tagsoup-1.2",
     ":json-20080701",
   ]
 }