Fix cpplint whitespace/comments issues

Change-Id: Iae286862c85fb8fd8901eae1204cd6d271d69496
diff --git a/compiler/driver/dex_compilation_unit.h b/compiler/driver/dex_compilation_unit.h
index facc9cb..5bf0086 100644
--- a/compiler/driver/dex_compilation_unit.h
+++ b/compiler/driver/dex_compilation_unit.h
@@ -111,6 +111,6 @@
   std::string symbol_;
 };
 
-} // namespace art
+}  // namespace art
 
 #endif  // ART_COMPILER_DRIVER_DEX_COMPILATION_UNIT_H_