gn: Generalize process_version() and move it to build/util

extensions/shell/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/features.gni")
 import("//build/config/ui.gni")
-
-# Technically, this directory should not depend on files from src/chrome, but
-# that's where the VERSION file is. This  should probably all be moved to
-# src/build.
-import("//chrome/version.gni")
+import("//build/util/process_version.gni")
 import("//testing/test.gni")
 import("//tools/grit/grit_rule.gni")
 
 assert(enable_extensions)
 
 grit("resources") {
   source = "app_shell_resources.grd"
   outputs = [
     "grit/app_shell_resources.h",
     "app_shell_resources.pak",
@@ skipping 251 matching lines @@
     deps += [ "//chromeos:test_support_without_gmock" ]
   }
 
   if (enable_nacl) {
     sources += [ "browser/shell_nacl_browser_delegate_unittest.cc" ]
   }
 }
 
 process_version("version_header") {
   template_file = "common/version.h.in"
+  sources = [
+    "//build/util/LASTCHANGE",
+    "//chrome/VERSION",
+  ]
   output = "$target_gen_dir/common/version.h"
 }
 
 if (is_mac) {
   # TODO(GYP) this should be a bundle. Lots of other stuff in this target.
   # Should be able to copy content shell framework (this is basically a
   # copy-paste of that target).
   shared_library("app_shell_framework") {
     testonly = true
     sources = [
@@ skipping 50 matching lines @@
     "//extensions/browser",
   ]
 
   if (is_chromeos) {
     deps += [
       "//chromeos:test_support",
       "//components/keyed_service/content",
     ]
   }
 }