Fix lineprocessor sample and include it in the gyp build.

samples/lineprocessor.cc

-// Copyright 2009 the V8 project authors. All rights reserved.
+// Copyright 2012 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
 //       with the distribution.
@@ skipping 415 matching lines @@
 
   char* res;
   {
 #ifdef SUPPORT_DEBUGGING
     v8::Unlocker unlocker;
 #endif
     res = fgets(buffer, kBufferSize, stdin);
   }
   if (res == NULL) {
     v8::Handle<v8::Primitive> t = v8::Undefined();
-    return reinterpret_cast<v8::Handle<v8::String>&>(t);
+    return v8::Handle<v8::String>(v8::String::Cast(*t));
   }
-  // remove newline char
+  // Remove newline char
   for (char* pos = buffer; *pos != '\0'; pos++) {
     if (*pos == '\n') {
       *pos = '\0';
       break;
     }
   }
   return v8::String::New(buffer);
 }