Allow d8 to run a script multiple times, each time with a new context.

src/d8.cc

 // 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
@@ skipping 1467 matching lines @@
                            : Testing::kStressTypeDeopt);
     int stress_runs = Testing::GetStressRuns();
     for (int i = 0; i < stress_runs && result == 0; i++) {
       printf("============ Stress %d/%d ============\n", i + 1, stress_runs);
       Testing::PrepareStressRun(i);
       options.last_run = (i == stress_runs - 1);
       result = RunMain(argc, argv);
     }
     printf("======== Full Deoptimization =======\n");
     Testing::DeoptimizeAll();
+  } else if (i::FLAG_stress_runs > 0) {
+    int stress_runs = i::FLAG_stress_runs;
+    for (int i = 0; i < stress_runs && result == 0; i++) {
+      printf("============ Run %d/%d ============\n", i + 1, stress_runs);
+      result = RunMain(argc, argv);
+    }
   } else {
     result = RunMain(argc, argv);
   }
 
 
 #if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
   // Run remote debugger if requested, but never on --test
   if (i::FLAG_remote_debugger && !options.test_shell) {
     InstallUtilityScript();
     RunRemoteDebugger(i::FLAG_debugger_port);
@@ skipping 25 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif