Fixed printing of JS code.

src/ostreams.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <algorithm>
+#include <cctype>
 #include <cmath>
 
 #include "src/base/platform/platform.h"  // For isinf/isnan with MSVC
 #include "src/ostreams.h"
 
 #if V8_OS_WIN
 #define snprintf sprintf_s
 #endif
 
 namespace v8 {
@@ skipping 142 matching lines @@
 
 
 OFStream& OFStream::flush() {
   if (f_) fflush(f_);
   return *this;
 }
 
 
 OStream& operator<<(OStream& os, const AsReversiblyEscapedUC16& c) {
   char buf[10];
-  const char* format = (0x20 <= c.value && c.value <= 0x7F) && (c.value != 0x52)
-                           ? "%c"
-                           : (c.value <= 0xff) ? "\\x%02x" : "\\u%04x";
+  const char* format =
+      (std::isprint(c.value) || std::isspace(c.value)) && c.value != '\\'
+          ? "%c"
+          : (c.value <= 0xff) ? "\\x%02x" : "\\u%04x";
   snprintf(buf, sizeof(buf), format, c.value);
   return os << buf;
 }
 
 
 OStream& operator<<(OStream& os, const AsUC16& c) {
   char buf[10];
-  const char* format = (0x20 <= c.value && c.value <= 0x7F)
-                           ? "%c"
-                           : (c.value <= 0xff) ? "\\x%02x" : "\\u%04x";
+  const char* format =
+      std::isprint(c.value) ? "%c" : (c.value <= 0xff) ? "\\x%02x" : "\\u%04x";
   snprintf(buf, sizeof(buf), format, c.value);
   return os << buf;
 }
 } }  // namespace v8::internal