Perform InterfaceProviderSpec intersection in the ServiceManager

services/service_manager/public/cpp/lib/interface_registry.cc

Index: services/service_manager/public/cpp/lib/interface_registry.cc
diff --git a/services/service_manager/public/cpp/lib/interface_registry.cc b/services/service_manager/public/cpp/lib/interface_registry.cc
index 91314a6e5300915f20fcf8c38f7eee5881e03eac..a903dc366feeef04e143e3b2b9c4b61b13db45c3 100644
--- a/services/service_manager/public/cpp/lib/interface_registry.cc
+++ b/services/service_manager/public/cpp/lib/interface_registry.cc
@@ -13,7 +13,29 @@
 namespace service_manager {
 namespace {
 
-// Returns the set of capabilities required from the target.
+void SerializeIdentity(const Identity& identity, std::stringstream* stream) {
+  *stream << identity.name() << "@" << identity.instance() << " run as: "
+          << identity.user_id();
+}
+
+void SerializeSpec(const InterfaceProviderSpec& spec,
+                   std::stringstream* stream) {
+  *stream << "  Providing:\n";
+  for (const auto& entry : spec.provides) {
+    *stream << "    capability: " << entry.first << " containing interfaces:\n";
+    for (const auto& interface_name : entry.second)
+      *stream << "      " << interface_name << "\n";
+  }
+  *stream << "\n  Requiring:\n";
+  for (const auto& entry : spec.requires) {
+    *stream << "    From: " << entry.first << ":\n";
+    for (const auto& capability_name : entry.second)
+      *stream << "      " << capability_name << "\n";
+  }
+}
+
+}  // namespace
+
 CapabilitySet GetRequestedCapabilities(const InterfaceProviderSpec& source_spec,
                                        const Identity& target) {
   CapabilitySet capabilities;
@@ -34,8 +56,6 @@ CapabilitySet GetRequestedCapabilities(const InterfaceProviderSpec& source_spec,
   return capabilities;
 }
 
-// Generates a single set of interfaces that is the union of all interfaces
-// exposed by the target for the capabilities requested by the source.
 InterfaceSet GetInterfacesToExpose(
     const InterfaceProviderSpec& source_spec,
     const Identity& target,
@@ -58,29 +78,6 @@ InterfaceSet GetInterfacesToExpose(
   return exposed_interfaces;
 }
 
-void SerializeIdentity(const Identity& identity, std::stringstream* stream) {
-  *stream << identity.name() << "@" << identity.instance() << " run as: "
-          << identity.user_id();
-}
-
-void SerializeSpec(const InterfaceProviderSpec& spec,
-                   std::stringstream* stream) {
-  *stream << "  Providing:\n";
-  for (const auto& entry : spec.provides) {
-    *stream << "    capability: " << entry.first << " containing interfaces:\n";
-    for (const auto& interface_name : entry.second)
-      *stream << "      " << interface_name << "\n";
-  }
-  *stream << "\n  Requiring:\n";
-  for (const auto& entry : spec.requires) {
-    *stream << "    From: " << entry.first << ":\n";
-    for (const auto& capability_name : entry.second)
-      *stream << "      " << capability_name << "\n";
-  }
-}
-
-}  // namespace
-
 InterfaceRegistry::InterfaceRegistry(const std::string& name)
     : binding_(this),
       name_(name),