[Sync] Rename csync namespace to syncer

sync/engine/build_commit_command_unittest.cc

Index: sync/engine/build_commit_command_unittest.cc
diff --git a/sync/engine/build_commit_command_unittest.cc b/sync/engine/build_commit_command_unittest.cc
index f92bcd0e42c315648e7c3f74fc6961c3568cb3d8..59e98eaa6723c54409e1854423de4f9053409a18 100644
--- a/sync/engine/build_commit_command_unittest.cc
+++ b/sync/engine/build_commit_command_unittest.cc
@@ -5,7 +5,7 @@
 #include "sync/engine/build_commit_command.h"
 #include "sync/test/engine/syncer_command_test.h"
 
-namespace csync {
+namespace syncer {
 
 // A test fixture for tests exercising ClearDataCommandTest.
 class BuildCommitCommandTest : public SyncerCommandTest {
@@ -102,6 +102,6 @@ TEST_F(BuildCommitCommandTest, InterpolatePosition) {
       command_.InterpolatePosition(0, BuildCommitCommand::GetGap()*2 + 1));
 }
 
-}  // namespace csync
+}  // namespace syncer