Create storage_unittests target.

storage/browser/BUILD.gn

Index: storage/browser/BUILD.gn
diff --git a/storage/browser/BUILD.gn b/storage/browser/BUILD.gn
index a4cc79a2e3f9fc92a217d83fc7fb9daaaee64a15..d76f52634a14db35ce0c8cfd9fe763cd4c53bf42 100644
--- a/storage/browser/BUILD.gn
+++ b/storage/browser/BUILD.gn
@@ -1,6 +1,7 @@
 # Copyright 2014 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("//testing/test.gni")
 
 component("browser") {
   output_name = "storage_browser"
@@ -215,3 +216,21 @@ executable("dump_file_system") {
     "//storage/common",
   ]
 }
+
+test("storage_unittests") {
+  sources = [
+    # Do NOT add storage/ tests here until this target is added to the build
+    # bots. http://crbug.com/653751
+
+    # If the sources list is empty, the win_clang builder fails.
+    # This file will be removed when the real tests are moved over from
+    # content_unittests to this target.
+    "crbug653751_unittest.cc",
+  ]
+
+  deps = [
+    "//base/test:run_all_unittests",
+    "//base/test:test_support",
+    "//testing/gtest",
+  ]
+}