First cut at "content handling" support in Mojo.

mojo/service_manager/background_service_loader.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 "mojo/service_manager/background_service_loader.h"
 
 #include "base/bind.h"
 #include "mojo/service_manager/service_manager.h"
 
 namespace mojo {
 
 class BackgroundServiceLoader::BackgroundLoader {
  public:
   explicit BackgroundLoader(ServiceLoader* loader) : loader_(loader) {}
   ~BackgroundLoader() {}
 
   void LoadService(ServiceManager* manager,
                    const GURL& url,
                    ScopedMessagePipeHandle shell_handle) {
-    loader_->LoadService(manager, url, shell_handle.Pass());
+    scoped_refptr<LoadServiceCallbacks> callbacks(
+        new ServiceLoader::SimpleLoadServiceCallbacks(shell_handle.Pass()));
+    loader_->LoadService(manager, url, callbacks);
   }
 
   void OnServiceError(ServiceManager* manager, const GURL& url) {
     loader_->OnServiceError(manager, url);
   }
 
  private:
   base::MessageLoop::Type message_loop_type_;
   ServiceLoader* loader_;  // Owned by BackgroundServiceLoader
 
@@ skipping 16 matching lines @@
         FROM_HERE,
         base::Bind(&BackgroundServiceLoader::ShutdownOnBackgroundThread,
                    base::Unretained(this)));
   }
   thread_.Stop();
 }
 
 void BackgroundServiceLoader::LoadService(
     ServiceManager* manager,
     const GURL& url,
-    ScopedMessagePipeHandle shell_handle) {
+    scoped_refptr<LoadServiceCallbacks> callbacks) {
   const int kDefaultStackSize = 0;
+
+  ScopedMessagePipeHandle shell_handle = callbacks->RegisterApplication();
+  if (!shell_handle.is_valid()) {
+    return;
+  }
+
   if (!thread_.IsRunning()) {
     thread_.StartWithOptions(
         base::Thread::Options(message_loop_type_, kDefaultStackSize));
   }
   thread_.message_loop()->PostTask(
       FROM_HERE,
       base::Bind(&BackgroundServiceLoader::LoadServiceOnBackgroundThread,
                  base::Unretained(this), manager, url,
-                 base::Owned(
-                    new ScopedMessagePipeHandle(shell_handle.Pass()))));
+                 base::Passed(&shell_handle)));
 }
 
 void BackgroundServiceLoader::OnServiceError(ServiceManager* manager,
                                              const GURL& url) {
   if (!thread_.IsRunning())
     thread_.Start();
   thread_.message_loop()->PostTask(
       FROM_HERE,
       base::Bind(&BackgroundServiceLoader::OnServiceErrorOnBackgroundThread,
                  base::Unretained(this), manager, url));
 }
 
 void BackgroundServiceLoader::LoadServiceOnBackgroundThread(
     ServiceManager* manager,
     const GURL& url,
-    ScopedMessagePipeHandle* shell_handle) {
+    ScopedMessagePipeHandle shell_handle) {
   if (!background_loader_)
     background_loader_ = new BackgroundLoader(loader_.get());
   background_loader_->LoadService(
-      manager, url, shell_handle->Pass());
+      manager, url, shell_handle.Pass());
 }
 
 void BackgroundServiceLoader::OnServiceErrorOnBackgroundThread(
     ServiceManager* manager,
     const GURL& url) {
   if (!background_loader_)
     background_loader_ = new BackgroundLoader(loader_.get());
   background_loader_->OnServiceError(manager, url);
 }
 
 void BackgroundServiceLoader::ShutdownOnBackgroundThread() {
   delete background_loader_;
   // Destroy |loader_| on the thread it's actually used on.
   loader_.reset();
 }
 
 }  // namespace mojo