[Sync] Add support for denoting which sessions types are enabled

We do this by sending the set of enabled types (those in the routing info) at
commit time via a new ClientConfigParams message.

BUG=170162
R=tim@chromium.org


Review URL: https://chromiumcodereview.appspot.com/11935002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@177775 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 17 insertions, 0 deletions

diff --git a/sync/engine/build_commit_command.cc b/sync/engine/build_commit_command.cc
index 9d1a4b9..ba356e8 100644
--- a/sync/engine/build_commit_command.cc
+++ b/sync/engine/build_commit_command.cc
@@ -97,6 +97,17 @@ void BuildCommitCommand::AddExtensionsActivityToMessage(
   }
 }
 
+void BuildCommitCommand::AddClientConfigParamsToMessage(
+    SyncSession* session, sync_pb::CommitMessage* message) {
+  const ModelSafeRoutingInfo& routing_info = session->routing_info();
+  sync_pb::ClientConfigParams* config_params = message->mutable_config_params();
+  for (std::map<ModelType, ModelSafeGroup>::const_iterator iter =
+          routing_info.begin(); iter != routing_info.end(); ++iter) {
+    int field_number = GetSpecificsFieldNumberFromModelType(iter->first);
+    config_params->mutable_enabled_type_ids()->Add(field_number);
+  }
+}
+
 namespace {
 void SetEntrySpecifics(MutableEntry* meta_entry,
                        sync_pb::SyncEntity* sync_entry) {
@@ -116,6 +127,7 @@ SyncerError BuildCommitCommand::ExecuteImpl(SyncSession* session) {
   commit_message->set_cache_guid(
       session->write_transaction()->directory()->cache_guid());
   AddExtensionsActivityToMessage(session, commit_message);
+  AddClientConfigParamsToMessage(session, commit_message);
 
   // Cache previously computed position values.  Because |commit_ids|
   // is already in sibling order, we should always hit this map after
diff --git a/sync/engine/build_commit_command.h b/sync/engine/build_commit_command.h
index b4190ca..253b6c0 100644
--- a/sync/engine/build_commit_command.h
+++ b/sync/engine/build_commit_command.h
@@ -53,6 +53,11 @@ class SYNC_EXPORT_PRIVATE BuildCommitCommand : public SyncerCommand {
 
   void AddExtensionsActivityToMessage(sessions::SyncSession* session,
                                       sync_pb::CommitMessage* message);
+
+  // Fills the config_params field of |message|.
+  void AddClientConfigParamsToMessage(sessions::SyncSession* session,
+                                      sync_pb::CommitMessage* message);
+
   // Helper for computing position.  Find the numeric position value
   // of the closest already-synced entry.  |direction| must be one of
   // NEXT_ID or PREV_ID; this parameter controls the search direction.