[Extensions] Don't require() a module for calling a method

extensions/renderer/module_system.h

 // 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.
 
 #ifndef EXTENSIONS_RENDERER_MODULE_SYSTEM_H_
 #define EXTENSIONS_RENDERER_MODULE_SYSTEM_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 165 matching lines @@
   // Retrieves the lazily defined field specified by |property| on a native
   // object.
   static void NativeLazyFieldGetter(
       v8::Local<v8::Name> property,
       const v8::PropertyCallbackInfo<v8::Value>& info);
 
   // Called when an exception is thrown but not caught.
   void HandleException(const v8::TryCatch& try_catch);
 
   void RequireForJs(const v8::FunctionCallbackInfo<v8::Value>& args);
-  v8::Local<v8::Value> RequireForJsInner(v8::Local<v8::String> module_name);
+
+  // Returns the module with the given |module_name|. If |create| is true, the
+  // module will be loaded if it hasn't been already. Otherwise, the module
+  // will only be returned if it has already been loaded.
+  v8::Local<v8::Value> RequireForJsInner(v8::Local<v8::String> module_name,
+                                         bool create);
 
   typedef v8::MaybeLocal<v8::Object>(ModuleSystem::*RequireFunction)(
       const std::string&);
   // Base implementation of a LazyFieldGetter which uses |require_fn| to require
   // modules.
   static void LazyFieldGetterInner(
       v8::Local<v8::String> property,
       const v8::PropertyCallbackInfo<v8::Value>& info,
       RequireFunction require_function);
 
@@ skipping 33 matching lines @@
   // gin::ModuleRegistryObserver overrides.
   void OnDidAddPendingModule(
       const std::string& id,
       const std::vector<std::string>& dependencies) override;
 
   // Marks any existing NativeHandler named |name| as clobbered.
   // See |clobbered_native_handlers_|.
   void ClobberExistingNativeHandler(const std::string& name);
 
   // Returns the v8::Function associated with the given module and method name.
+  // This will *not* load a module if it hasn't been loaded already.
   v8::Local<v8::Function> GetModuleFunction(const std::string& module_name,
                                             const std::string& method_name);
 
   ScriptContext* context_;
 
   // A map from module names to the JS source for that module. GetSource()
   // performs a lookup on this map.
   const SourceMap* const source_map_;
 
   // A map from native handler names to native handlers.
@@ skipping 26 matching lines @@
   std::set<std::string> loaded_modules_;
 
   base::WeakPtrFactory<ModuleSystem> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ModuleSystem);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_MODULE_SYSTEM_H_