Make V8ValueConverter.FromV8Value behave similarly to JSON.stringify

chrome/renderer/resources/extensions/schema_generated_bindings.js

Index: chrome/renderer/resources/extensions/schema_generated_bindings.js
diff --git a/chrome/renderer/resources/extensions/schema_generated_bindings.js b/chrome/renderer/resources/extensions/schema_generated_bindings.js
index ecf46f31011c39925034a6d11c003ba5c902d86b..76bda1ea52e2ba00c24ebebb5b315cc61c22858c 100644
--- a/chrome/renderer/resources/extensions/schema_generated_bindings.js
+++ b/chrome/renderer/resources/extensions/schema_generated_bindings.js
@@ -311,9 +311,12 @@
             if (this.handleRequest) {
               retval = this.handleRequest.apply(this, args);
             } else {
+              var optArgs = {
+                customCallback: this.customCallback
+              };
               retval = sendRequest(this.name, args,
                                    this.definition.parameters,
-                                   {customCallback: this.customCallback});
+                                   optArgs);
             }
 
             // Validate return value if defined - only in debug.