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

src/platform.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 42 matching lines @@
 enum {
   FP_NAN,
   FP_INFINITE,
   FP_ZERO,
   FP_SUBNORMAL,
   FP_NORMAL
 };
 
 #define INFINITY HUGE_VAL
 
-namespace v8 { namespace internal {
+namespace v8 {
+namespace internal {
 int isfinite(double x);
 } }
 int isnan(double x);
 int isinf(double x);
 int isless(double x, double y);
 int isgreater(double x, double y);
 int fpclassify(double x);
 int signbit(double x);
 
 int strncasecmp(const char* s1, const char* s2, int n);
@@ skipping 24 matching lines @@
 // only when compiling with GCC versions affected by the bug (2.96.x - 4.0.x)
 // __GNUC_PREREQ is not defined in GCC for Mac OS X, so we define our own macro
 #if __GNUC_VERSION__ >= 29600 && __GNUC_VERSION__ < 40100
 #include <limits>
 #undef INFINITY
 #define INFINITY std::numeric_limits<double>::infinity()
 #endif
 
 #endif  // __GNUC__
 
-namespace v8 { namespace internal {
+namespace v8 {
+namespace internal {
 
 double ceiling(double x);
 
 // Forward declarations.
 class Socket;
 
 // ----------------------------------------------------------------------------
 // OS
 //
 // This class has static methods for the different platform specific
@@ skipping 410 matching lines @@
   bool active_;
   PlatformData* data_;  // Platform specific data.
   DISALLOW_IMPLICIT_CONSTRUCTORS(Sampler);
 };
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal
 
 #endif  // V8_PLATFORM_H_