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

src/x64/ic-x64.cc

 // Copyright 2009 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 14 matching lines @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "v8.h"
 
 #include "codegen-inl.h"
 #include "ic-inl.h"
 #include "runtime.h"
 #include "stub-cache.h"
 
-namespace v8 { namespace internal {
+namespace v8 {
+namespace internal {
 
 
 void KeyedLoadIC::ClearInlinedVersion(Address address) {
   UNIMPLEMENTED();
 }
 
 void KeyedLoadIC::Generate(MacroAssembler* masm,
                            ExternalReference const& f) {
   masm->int3();  // UNIMPLEMENTED.
 }
@@ skipping 120 matching lines @@
 
 void StoreIC::GenerateExtendStorage(MacroAssembler* masm) {
   masm->int3();  // UNIMPLEMENTED.
 }
 
 void StoreIC::GenerateMegamorphic(MacroAssembler* masm) {
   masm->int3();  // UNIMPLEMENTED.
 }
 
 } }  // namespace v8::internal