Make //blimp/client/app a real embedder of //blimp/client/public

blimp/client/core/common/BUILD.gn

 # Copyright 2016 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.
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
 
 if (is_android) {
   android_library("common_java") {
     visibility = [
-      "//blimp/client/app/*",  # TODO(nyquist): Remove this. See crbug/651964.
+      "//blimp/client/app:blimp_test_java_core_deps",
       "//blimp/client/core/*",
     ]
 
     java_files = [ "android/java/src/org/chromium/blimp/core/common/PreferencesUtil.java" ]
 
     deps = [
       "//base:base_java",
       "//blimp/client/public:public_headers_java",
     ]
   }
 }