Update tests to use std::isnan instead of isnan

test/cctest/test-log.cc

 // Copyright 2006-2009 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 10 matching lines @@
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // 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.
 //
 // Tests of logging functions from log.h
 
 #ifdef __linux__
-#include <math.h>
 #include <pthread.h>
 #include <signal.h>
 #include <unistd.h>
+#include <cmath>
 #endif  // __linux__
 
 #include "v8.h"
 #include "log.h"
 #include "cpu-profiler.h"
 #include "natives.h"
 #include "v8threads.h"
 #include "v8utils.h"
 #include "cctest.h"
 #include "vm-state-inl.h"
@@ skipping 520 matching lines @@
     v8::Local<v8::String> s = result->ToString();
     i::ScopedVector<char> data(s->Length() + 1);
     CHECK_NE(NULL, data.start());
     s->WriteAscii(data.start());
     printf("%s\n", data.start());
     // Make sure that our output is written prior crash due to CHECK failure.
     fflush(stdout);
     CHECK(false);
   }
 }