[Sync] Move sync/{internal_api,syncable} into syncer namespace

sync/engine/build_commit_command.cc

Index: sync/engine/build_commit_command.cc
diff --git a/sync/engine/build_commit_command.cc b/sync/engine/build_commit_command.cc
index f3c0a9f0f5586281ff4d19174162aa04b1d8f509..69f94ec4db7b47fd8a9eb033b2fa43f98fbd6710 100644
--- a/sync/engine/build_commit_command.cc
+++ b/sync/engine/build_commit_command.cc
@@ -23,6 +23,10 @@
 using std::set;
 using std::string;
 using std::vector;
+
+namespace syncer {
+
+using sessions::SyncSession;
 using syncable::Entry;
 using syncable::IS_DEL;
 using syncable::SERVER_POSITION_IN_PARENT;
@@ -33,10 +37,6 @@ using syncable::MutableEntry;
 using syncable::SPECIFICS;
 using syncable::UNSPECIFIED;
 
-namespace syncer {
-
-using sessions::SyncSession;
-
 // static
 int64 BuildCommitCommand::GetFirstPosition() {
   return std::numeric_limits<int64>::min();