Support reading multiple InterfaceProviderSpecs from manifests

services/service_manager/public/interfaces/interface_provider_spec.mojom

 // Copyright 2016 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.
 
 module service_manager.mojom;
 
 // Defines a set of Mojo interfaces. The string value is the fully qualified
 // name of the interface in the form "module::path::InterfaceName". We don't
 // represent this as a bare array in-situ in mojom because we rely on type maps
 // to generate a set container in C++ which is unavailable for a bare array.
@@ skipping 19 matching lines @@
   // non-empty, or ["*"], which means allow access to all interfaces.
   map<string, InterfaceSet> provides;
 
   // The services this service needs to speak to, and the capabilities it
   // requires from each.
   // A map of service name -> collection of required capabilities. "*" is also
   // supported as the key, which supplies a set of capabilities required from
   // all services in addition to specific ones specified.
   map<string, CapabilitySet> requires;
 };
+
+// The name of the InterfaceProviderSpec in service manifests used by the
+// Service Manager to control capabilities & interfaces exposed between
+// services via Connector.
+const string kServiceManager_ConnectorSpec = "service_manager:connector";