Various extension-related cleanup and simplifications.

src/extensions/free-buffer-extension.h

Index: src/extensions/free-buffer-extension.h
diff --git a/src/extensions/free-buffer-extension.h b/src/extensions/free-buffer-extension.h
index 22d466f61e02b4e8367dfc9d06f00095aa5efe02..26ff7d1bb0cb2952ac1f8a1a67480067f7b73551 100644
--- a/src/extensions/free-buffer-extension.h
+++ b/src/extensions/free-buffer-extension.h
@@ -35,13 +35,12 @@ namespace internal {
 
 class FreeBufferExtension : public v8::Extension {
  public:
-  explicit FreeBufferExtension(const char* source)
-      : v8::Extension("v8/free-buffer", source) {}
+  FreeBufferExtension()
+      : v8::Extension("v8/free-buffer", "native function freeBuffer();") {}
   virtual v8::Handle<v8::FunctionTemplate> GetNativeFunctionTemplate(
       v8::Isolate* isolate,
       v8::Handle<v8::String> name);
   static void FreeBuffer(const v8::FunctionCallbackInfo<v8::Value>& args);
-  static void Register();
 };
 
 } }  // namespace v8::internal