ash: Refactor touch hud drawing to ash/touch_hud as a separate component.

ash/touch_hud/BUILD.gn

Index: ash/touch_hud/BUILD.gn
diff --git a/ash/touch_hud/BUILD.gn b/ash/touch_hud/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..b3befb472fce8a3ff6de864611d31d8c85a82ae3
--- /dev/null
+++ b/ash/touch_hud/BUILD.gn
@@ -0,0 +1,23 @@
+# Copyright 2016 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")
+
+component("touch_hud") {
+  sources = [
+    "ash_touch_hud_export.h",
+    "touch_hud_renderer.cc",
+    "touch_hud_renderer.h",
+  ]
+
+  defines = [ "ASH_TOUCH_HUD_IMPLEMENTATION" ]
+
+  deps = [
+    "//base",
+    "//skia",
+    "//ui/events",
+    "//ui/gfx",
+    "//ui/views",
+  ]
+}