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

extensions/renderer/module_system.cc

 // Copyright 2014 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.
 
 #include "extensions/renderer/module_system.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/stl_util.h"
@@ skipping 83 matching lines @@
     }
     Fatal(context_, CreateExceptionString(try_catch) + "{" + stack_trace + "}");
   }
 };
 
 // Sets a property on the "exports" object for bindings. Called by JS with
 // exports.$set(<key>, <value>).
 void SetExportsProperty(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   v8::Local<v8::Object> obj = args.This();
-  DCHECK_EQ(2, args.Length());
-  DCHECK(args[0]->IsString());
+  CHECK_EQ(2, args.Length());
+  CHECK(args[0]->IsString());
   v8::Maybe<bool> result =
       obj->DefineOwnProperty(args.GetIsolate()->GetCurrentContext(),
                              args[0]->ToString(), args[1], v8::ReadOnly);
   if (!result.FromMaybe(false))
     LOG(ERROR) << "Failed to set private property on the export.";
 }
 
 }  // namespace
 
 std::string ModuleSystem::ExceptionHandler::CreateExceptionString(
@@ skipping 630 matching lines @@
 
 void ModuleSystem::ClobberExistingNativeHandler(const std::string& name) {
   NativeHandlerMap::iterator existing_handler = native_handler_map_.find(name);
   if (existing_handler != native_handler_map_.end()) {
     clobbered_native_handlers_.push_back(existing_handler->second);
     native_handler_map_.erase(existing_handler);
   }
 }
 
 }  // namespace extensions