Draw nicer arrows when the scrollbar buttons are not square.

ui/native_theme/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("native_theme") {
   sources = [
     "common_theme.cc",
     "common_theme.h",
     "native_theme.cc",
     "native_theme.h",
     "native_theme_android.cc",
     "native_theme_android.h",
     "native_theme_base.cc",
@@ skipping 39 matching lines @@
     "//ui/resources",
   ]
 
   if (is_mac) {
     libs = [
       "CoreGraphics.framework",
       "AppKit.framework",
     ]
   }
 }
+
+test("native_theme_unittests") {
+  sources = []
+
+  if (use_aura) {
+    sources += [ "native_theme_aura_unittest.cc" ]
+  }
+
+  if (is_mac) {
+    sources += [ "native_theme_mac_unittest.cc" ]
+  }
+
+  deps = [
+    ":native_theme",
+    "//base/test:run_all_unittests",
+    "//base/test:test_support",
+    "//skia:skia",
+    "//testing/gtest",
+    "//ui/gfx/geometry:geometry",
+  ]
+}