Revert of PPAPI: Never re-enter JavaScript for PostMessage.

ppapi/tests/test_message_handler.cc

Index: ppapi/tests/test_message_handler.cc
diff --git a/ppapi/tests/test_message_handler.cc b/ppapi/tests/test_message_handler.cc
index c8132e69fadbc48457aa497773e492b92ff266d6..0483a6b0cd499f4ec52fd0468c5ad225f083b42f 100644
--- a/ppapi/tests/test_message_handler.cc
+++ b/ppapi/tests/test_message_handler.cc
@@ -266,8 +266,13 @@
     js_code +=      values_to_test[i];
     js_code +=    " result: \" + result);\n";
   }
+  // TODO(dmichael): Setting a property uses GetInstanceObject, which sends sync
+  // message, which can get interrupted with message to eval script, etc.
+  // FINISHED_WAITING message can therefore jump ahead. This test is
+  // currently carefully crafted to avoid races by doing all the JS in one call.
+  // That should be fixed before this API goes to stable. See crbug.com/384528
+  js_code += "plugin.postMessage('FINISHED_TEST');\n";
   instance_->EvalScript(js_code);
-  instance_->EvalScript("plugin.postMessage('FINISHED_TEST');\n");
   handler.WaitForTestFinishedMessage();
   handler.Unregister();
   ASSERT_SUBTEST_SUCCESS(handler.WaitForDestroy());