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

src/x64/assembler-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 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.
 
 #include "v8.h"
 
 #include "macro-assembler.h"
 
-namespace v8 { namespace internal {
+namespace v8 {
+namespace internal {
 
 Register no_reg = { -1 };
 
 
 // Safe default is no features.
 uint64_t CpuFeatures::supported_ = 0;
 uint64_t CpuFeatures::enabled_ = 0;
 
 void CpuFeatures::Probe()  {
   // TODO(X64): UNIMPLEMENTED
@@ skipping 268 matching lines @@
 #include "regexp-macro-assembler.h"
 #include "regexp-stack.h"
 #include "register-allocator-inl.h"
 #include "register-allocator.h"
 #include "runtime.h"
 #include "scopes.h"
 #include "serialize.h"
 #include "stub-cache.h"
 #include "unicode.h"
 
-namespace v8 { namespace internal {
+namespace v8 {
+namespace internal {
 
 void ArgumentsAccessStub::GenerateNewObject(MacroAssembler* a) {
   UNIMPLEMENTED();
 }
 
 void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* a) {
   UNIMPLEMENTED();
 }
 
 void ArgumentsAccessStub::GenerateReadLength(MacroAssembler* a) {
@@ skipping 239 matching lines @@
   UNIMPLEMENTED();
   return NULL;
 }
 
 byte* JavaScriptFrame::GetCallerStackPointer() const {
   UNIMPLEMENTED();
   return NULL;
 }
 
 } }  // namespace v8::internal