Convert test_support source sets to static libs

chrome/app/BUILD.gn

 # 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("//build/config/ui.gni")
 import("//mojo/public/mojo_application_manifest.gni")
 import("//tools/grit/grit_rule.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
@@ skipping 294 matching lines @@
   use_qualified_include = true
   outputs = [
     "grit/settings_google_chrome_strings.h",
 
     # These strings are not being treated as strings because they are
     # not translated (English only), this should change in late 2015.
     "settings_google_chrome_strings.pak",
   ]
 }
 
-source_set("test_support") {
+static_library("test_support") {
   testonly = true
   visibility = [ "//chrome/test:test_support" ]
 
   sources = [
     "chrome_main_delegate.cc",
     "chrome_main_delegate.h",
   ]
 
   deps = [
     "//base",
@@ skipping 61 matching lines @@
     base_deps = [ "//content/public/app:renderer_manifest" ]
   }
 
   group("mojo_manifests") {
     data_deps = [
       ":chrome_manifest",
       ":chrome_renderer_manifest",
     ]
   }
 }