Remove unused variable in mksnapshot.cc.

src/mksnapshot.cc

 // 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 327 matching lines @@
       i += read;
     }
     fclose(file);
     Local<String> source = String::New(chars);
     TryCatch try_catch;
     Local<Script> script = Script::Compile(source);
     if (try_catch.HasCaught()) {
       fprintf(stderr, "Failure compiling '%s' (see above)\n", name);
       exit(1);
     }
-    Handle<Value> ret = script->Run();
+    script->Run();
     if (try_catch.HasCaught()) {
       fprintf(stderr, "Failure running '%s'\n", name);
       Local<Message> message = try_catch.Message();
       Local<String> message_string = message->Get();
       Local<String> message_line = message->GetSourceLine();
       int len = 2 + message_string->Utf8Length() + message_line->Utf8Length();
       char* buf = new char(len);
       message_string->WriteUtf8(buf);
       fprintf(stderr, "%s at line %d\n", buf, message->GetLineNumber());
       message_line->WriteUtf8(buf);
@@ skipping 43 matching lines @@
   sink.WriteSpaceUsed(
       partial_ser.CurrentAllocationAddress(i::NEW_SPACE),
       partial_ser.CurrentAllocationAddress(i::OLD_POINTER_SPACE),
       partial_ser.CurrentAllocationAddress(i::OLD_DATA_SPACE),
       partial_ser.CurrentAllocationAddress(i::CODE_SPACE),
       partial_ser.CurrentAllocationAddress(i::MAP_SPACE),
       partial_ser.CurrentAllocationAddress(i::CELL_SPACE),
       partial_ser.CurrentAllocationAddress(i::LO_SPACE));
   return 0;
 }