shill: Rename MergeService to ConfigureService

Collateral changes: Use ContainsService internally to profile's
ConfigureService.  Refrain from using Service::GetStorageIdentifier
directly.  I can think of scenarios coming up where it is important
for the Service to determine for itself whether a StorageInterface
contains anything it can use.

BUG=chromium-os:22422
TEST=ReRun Unit Tests

Change-Id: I34c6cb272c1540ab1e8d8d9bed4083b52e20f75e
Reviewed-on: https://gerrit.chromium.org/gerrit/11099
Commit-Ready: Paul Stewart <pstew@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>
diff --git a/profile.cc b/profile.cc
index 46d979e..d87bbf2 100644
--- a/profile.cc
+++ b/profile.cc
@@ -146,15 +146,15 @@
   return service->Save(storage_.get()) && storage_->Flush();
 }
 
-bool Profile::MergeService(const ServiceRefPtr &service) {
-  if (!storage_->ContainsGroup(service->GetStorageIdentifier()))
+bool Profile::ConfigureService(const ServiceRefPtr &service) {
+  if (!ContainsService(service))
     return false;
   service->set_profile(this);
   return service->Load(storage_.get());
 }
 
 bool Profile::ContainsService(const ServiceConstRefPtr &service) {
-  return storage_->ContainsGroup(service->GetStorageIdentifier());
+  return service->IsLoadableFrom(storage_.get());
 }
 
 bool Profile::IsValidIdentifierToken(const std::string &token) {