Improve GN header checker, make //ui pass.

ui/gfx/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")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
@@ skipping 203 matching lines @@
     "win/singleton_hwnd.cc",
     "win/singleton_hwnd.h",
     "win/window_impl.cc",
     "win/window_impl.h",
   ]
 
   defines = [ "GFX_IMPLEMENTATION" ]
 
   deps = [
     ":gfx_export",
-    "//base",
     "//base:i18n",
     "//base:base_static",
     "//base/third_party/dynamic_annotations",
     "//skia",
     "//third_party/harfbuzz-ng",
-    "//third_party/icu:icui18n",
-    "//third_party/icu:icuuc",
     "//third_party/libpng",
     "//third_party/zlib",
     "//ui/gfx/geometry",
   ]
-  forward_dependent_configs_from = [ "//skia" ]
+  public_deps = [
+    "//base",
+    "//skia",
+    "//third_party/icu",
+  ]
 
   # Text rendering conditions (complicated so separated out).
   if (is_android || is_ios) {
     # We don't support RenderText on these platforms.
   } else {
     # These text rendering files are supported everywhere text rendering is.
     sources += [
       "render_text.cc",
       "render_text.h",
       "render_text_harfbuzz.cc",
@@ skipping 124 matching lines @@
     "image/image_unittest_util_ios.mm",
     "image/image_unittest_util_mac.mm",
     "test/fontconfig_util_linux.cc",
     "test/fontconfig_util_linux.h",
     "test/gfx_util.cc",
     "test/gfx_util.h",
     "test/ui_cocoa_test_helper.h",
     "test/ui_cocoa_test_helper.mm",
   ]
 
+  public_deps = [
+    ":gfx",
+  ]
+
   deps = [
-    ":gfx",
     "//base",
     "//base/test:test_support",
     "//skia",
     "//testing/gtest",
     "//ui/gfx/geometry",
   ]
 
   if (is_ios) {
     # The cocoa files don't apply to iOS.
     sources -= [
@@ skipping 64 matching lines @@
   }
 
   deps = [
     ":gfx",
     ":test_support",
     "//base",
     "//base/test:test_support",
     "//skia",
     "//third_party/icu:icuuc",
     "//third_party/libpng",
+    "//third_party/zlib",
     "//testing/gtest",
     "//ui/base",
     "//ui/gfx/geometry",
     "//ui/resources:ui_test_pak",
   ]
 
   if (use_pango) {
     sources += [
       "font_render_params_linux_unittest.cc",
       "platform_font_pango_unittest.cc",
@@ skipping 74 matching lines @@
 if (is_android) {
   generate_jni("gfx_jni_headers") {
     sources = [
       "../android/java/src/org/chromium/ui/gfx/BitmapHelper.java",
       "../android/java/src/org/chromium/ui/gfx/DeviceDisplayInfo.java",
       "../android/java/src/org/chromium/ui/gfx/ViewConfigurationHelper.java",
     ]
     jni_package = "gfx"
   }
 }