Split nested namespaces declaration in two lines in accordance with C++ Style Guide.

src/flags.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 11 matching lines @@
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #ifndef V8_FLAGS_H_
 #define V8_FLAGS_H_
 
 #include "checks.h"
 
-namespace v8 { namespace internal {
+namespace v8 {
+namespace internal {
 
 // Declare all of our flags.
 #define FLAG_MODE_DECLARE
 #include "flag-definitions.h"
 
 // The global list of all flags.
 class FlagList {
  public:
   // The list of all flags with a value different from the default
   // and their values. The format of the list is like the format of the
@@ skipping 28 matching lines @@
   // Reset all flags to their default value.
   static void ResetAllFlags();
 
   // Print help to stdout with flags, types, and default values.
   static void PrintHelp();
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_FLAGS_H_