Convert utility process extension Unpacker IPC to mojo

extensions/DEPS

 include_rules = [
   # Do not add Chrome dependencies. Much work went into removing them.
   "+components/browsing_data",
   "+components/crx_file",
   "+components/guest_view",
   "+components/prefs",
   "+components/url_matcher",
   "+components/version_info",
   "-content",
   "+content/grit/content_resources.h",
   "+content/public/common",
   "+content/public/test",
   "+crypto",
   "-extensions/components",
   "+extensions/test",
   "+grit/extensions_renderer_resources.h",
   "+grit/extensions_resources.h",
   "+mojo/public",
+  "+services/service_manager/public",
   "+testing",
   "+third_party/skia/include",
 
   # Minimal UI dependencies. There are two good rules for UI dependencies here:
   #
   #   1) UI components should only be added as they are needed, and
   #   2) if //content doesn't allow it, //extensions probably won't allow it.
   #      (see for example ui/views)
   "-ui",
   "+ui/base",
@@ skipping 22 matching lines @@
     "+chrome/browser/extensions/test_extension_prefs.h",
     "+chrome/browser/extensions/test_extension_system.h",
     "+chrome/browser/ui/browser.h",
     "+chrome/common/chrome_switches.h",
     "+chrome/common/extensions/features/feature_channel.h",
     "+chrome/test/base/chrome_render_view_test.h",
     "+chrome/test/base/testing_profile.h",
     "+chrome/test/base/ui_test_utils.h",
   ],
 }