Convert some GN test support targets to static libs.

ui/compositor/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("//testing/test.gni")
 
 component("compositor") {
   sources = [
     "callback_layer_animation_observer.cc",
@@ skipping 78 matching lines @@
     # TODO(sky): before we make this real need to remove
     # IDR_BITMAP_BRUSH_IMAGE.
     deps += [
       "//third_party/angle:libEGL",
       "//third_party/angle:libGLESv2",
       "//ui/resources",
     ]
   }
 }
 
-source_set("test_support") {
+static_library("test_support") {
   testonly = true
   sources = [
     "test/context_factories_for_test.cc",
     "test/context_factories_for_test.h",
     "test/draw_waiter_for_test.cc",
     "test/draw_waiter_for_test.h",
     "test/in_process_context_factory.cc",
     "test/in_process_context_factory.h",
     "test/in_process_context_provider.cc",
     "test/in_process_context_provider.h",
@@ skipping 86 matching lines @@
     "//ui/base",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gl",
     "//ui/resources",
   ]
   if (is_linux) {
     deps += [ "//third_party/mesa:osmesa" ]
   }
 }