Convert utility process extension Unpacker IPC to mojo

chrome/utility/extensions/extensions_handler.cc

 // 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.
 
 #include "chrome/utility/extensions/extensions_handler.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 167 matching lines @@
 #endif  // defined(OS_WIN)
 
 }  // namespace
 
 namespace extensions {
 
 ExtensionsHandler::ExtensionsHandler() {
   ExtensionsClient::Set(ChromeExtensionsClient::GetInstance());
 }
 
-ExtensionsHandler::~ExtensionsHandler() {
-}
+ExtensionsHandler::~ExtensionsHandler() = default;
 
 // static
 void ExtensionsHandler::PreSandboxStartup() {
   // Initialize media libraries for media file validation.
   media::InitializeMediaLibrary();
 }
 
 // static
+void ExtensionsHandler::UtilityThreadStarted() {
+  UtilityHandler::UtilityThreadStarted();

[Devlin, 2017/02/14 17:24:59]

Why do we need this method, as opposed to calling
UtilityHandler::UtilityThreadStarted() directly?

[Noel Gordon, 2017/02/15 17:28:08]

ExtensionsHandler owns a UtilityHandler utility_handler_, so layering, we let
ExtensionsHandler control it.  And similarly below in
ExtensionsHandler::ExposeInterfacesToBrowser.

[Devlin, 2017/02/17 15:53:56]

I don't quite follow - this is a static method, so ownership in member variables
doesn't really matter.  In ExposeInterfacesToBrowser(), the layering is
important, because it adds extra logic that UtilityHandler doesn't do.  Here, it
just seems to add an extra function call.

+}
+
+// static
 void ExtensionsHandler::ExposeInterfacesToBrowser(
     service_manager::InterfaceRegistry* registry,
     ChromeContentUtilityClient* utility_client,
     bool running_elevated) {
+  UtilityHandler::ExposeInterfacesToBrowser(registry, running_elevated);
   // If our process runs with elevated privileges, only add elevated Mojo
   // services to the interface registry.
   if (running_elevated) {
 #if defined(OS_WIN)
     registry->AddInterface(base::Bind(&RemovableStorageWriterImpl::Create));
     registry->AddInterface(base::Bind(&WiFiCredentialsGetterImpl::Create));
 #endif
     return;
   }
 
@@ skipping 80 matching lines @@
   picasa::PicasaAlbumsIndexer indexer(album_uids);
   indexer.ParseFolderINI(folders_inis);
   content::UtilityThread::Get()->Send(
       new ChromeUtilityHostMsg_IndexPicasaAlbumsContents_Finished(
           indexer.albums_images()));
   ReleaseProcessIfNeeded();
 }
 #endif  // defined(OS_WIN) || defined(OS_MACOSX)
 
 }  // namespace extensions