[Extensions] Don't allow gin::Define to be overridden

extensions/renderer/v8_helpers.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef EXTENSIONS_RENDERER_V8_HELPERS_H_
 #define EXTENSIONS_RENDERER_V8_HELPERS_H_
 
 #include <string.h>
 
+#include "base/strings/string_number_conversions.h"
 #include "v8/include/v8.h"
 
 namespace extensions {
 namespace v8_helpers {
 
 // Helper functions for V8 APIs.
 
 // Converts |str| to a V8 string. Returns true on success.
 inline bool ToV8String(v8::Isolate* isolate,
                        const char* str,
@@ skipping 29 matching lines @@
 // Returns true if |maybe| is both a value, and that value is true.
 inline bool IsTrue(v8::Maybe<bool> maybe) {
   return maybe.IsJust() && maybe.FromJust();
 }
 
 // Returns true if |value| is empty or undefined.
 inline bool IsEmptyOrUndefied(v8::Local<v8::Value> value) {
   return value.IsEmpty() || value->IsUndefined();
 }
 
-// SetProperty() family wraps V8::Object::Set(). Returns true on success.
+// SetProperty() family wraps V8::Object::DefineOwnProperty().
+// Returns true on success.
 inline bool SetProperty(v8::Local<v8::Context> context,
                         v8::Local<v8::Object> object,
-                        v8::Local<v8::Value> key,
+                        v8::Local<v8::String> key,
                         v8::Local<v8::Value> value) {
-  return IsTrue(object->Set(context, key, value));
+  return IsTrue(object->DefineOwnProperty(context, key, value));
 }
 
 inline bool SetProperty(v8::Local<v8::Context> context,
-                        v8::Local<v8::Object> object,
-                        uint32_t index,
-                        v8::Local<v8::Value> value) {
-  return IsTrue(object->Set(context, index, value));
-}
-
-inline bool SetProperty(v8::Local<v8::Context> context,
                         v8::Local<v8::Object> object,
                         const char* key,
                         v8::Local<v8::Value> value) {
   v8::Local<v8::String> v8_key;
   if (!ToV8String(context->GetIsolate(), key, &v8_key))
     return false;
   return SetProperty(context, object, v8_key, value);
 }
 
+inline bool SetProperty(v8::Local<v8::Context> context,
+                        v8::Local<v8::Object> object,
+                        uint32_t index,
+                        v8::Local<v8::Value> value) {
+  return SetProperty(context, object, base::UintToString(index).c_str(), value);
+}
+
 // GetProperty() family calls V8::Object::Get() and extracts a value from
 // returned MaybeLocal. Returns true on success.
 template <typename Key>
 inline bool GetProperty(v8::Local<v8::Context> context,
                         v8::Local<v8::Object> object,
                         Key key,
                         v8::Local<v8::Value>* out) {
   return object->Get(context, key).ToLocal(out);
 }
 
@@ skipping 32 matching lines @@
                          int argc,
                          v8::Local<v8::Value> argv[],
                          v8::Local<v8::Value>* out) {
   return function->Call(context, recv, argc, argv).ToLocal(out);
 }
 
 }  // namespace v8_helpers
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_V8_HELPERS_H_