Pass application ids via AcceptConnection & ConnectToApplication callback.

mojo/shell/package_manager/package_manager_impl.cc

 // Copyright 2015 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/shell/package_manager/package_manager_impl.h"
 
 #include <stdint.h>
 
 #include <utility>
 
@@ skipping 111 matching lines @@
                                      target_url,
                                      target_filter,
                                      &content_handler_identity,
                                      &response)) {
     ContentHandlerConnection* connection =
         GetContentHandler(content_handler_identity, source);
     connection->StartApplication(std::move(*application_request),
                                  std::move(response));
     return connection->id();
   }
-  return Shell::kInvalidContentHandlerID;
+  return Shell::kInvalidApplicationID;
 }
 
 GURL PackageManagerImpl::ResolveURL(const GURL& url) {
   return url_resolver_.get() ? url_resolver_->ResolveMojoURL(url) : url;
 }
 
 bool PackageManagerImpl::ShouldHandleWithContentHandler(
   Fetcher* fetcher,
   const GURL& target_url,
   const CapabilityFilter& target_filter,
@@ skipping 75 matching lines @@
 void PackageManagerImpl::OnContentHandlerConnectionClosed(
     ContentHandlerConnection* connection) {
   // Remove the mapping.
   auto it = identity_to_content_handler_.find(connection->identity());
   DCHECK(it != identity_to_content_handler_.end());
   identity_to_content_handler_.erase(it);
 }
 
 }  // namespace shell
 }  // namespace mojo