Improve GN header checker, make //ui pass.

cc/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.
 
 component("cc") {
   sources = [
     "animation/animation.cc",
     "animation/animation.h",
     "animation/animation_curve.cc",
     "animation/animation_curve.h",
@@ skipping 606 matching lines @@
     "test/test_web_graphics_context_3d.h",
     "test/tiled_layer_test_common.cc",
     "test/tiled_layer_test_common.h",
   ]
 
   include_dirs = [
     ".",
     "test",
   ]
 
+  public_deps = [
+    ":cc",
+  ]
   deps = [
     "//base",
     "//base/third_party/dynamic_annotations",
     "//gpu:test_support",
     "//gpu/command_buffer/client:gles2_c_lib",
     "//gpu/command_buffer/client:gles2_implementation",
     "//gpu/command_buffer/client:gl_in_process_context",
     "//gpu/command_buffer/common:gles2_utils",
     "//gpu/skia_bindings",
     "//skia",
@@ skipping 181 matching lines @@
     "//gpu/command_buffer/common:gles2_utils",
     "//media",
     "//skia",
     "//testing/gmock",
     "//testing/gtest",
     "//testing/perf",
     "//ui/gfx",
     "//ui/gfx/geometry",
   ]
 }