[gin] Use variadic templates in gin/function_template.h

gin/wrappable_unittest.cc

Index: gin/wrappable_unittest.cc
diff --git a/gin/wrappable_unittest.cc b/gin/wrappable_unittest.cc
index 0e10c326b5ca438dc725d3e1edb343a7f0ad9141..3ee50576e91afbb061c306029f4303f7f18d4897 100644
--- a/gin/wrappable_unittest.cc
+++ b/gin/wrappable_unittest.cc
@@ -97,11 +97,11 @@ class MyCallableObject : public Wrappable<MyCallableObject> {
   virtual ~MyCallableObject() {
   }
 
-  void Call(int val, const gin::Arguments& arguments) {
+  void Call(int val1, int val2, int val3, const gin::Arguments& arguments) {
     if (arguments.IsConstructCall())
       arguments.ThrowTypeError("Cannot be called as constructor.");
     else
-      result_ = val;
+      result_ = val1;
   }
 
   int result_;
@@ -233,7 +233,7 @@ TEST_F(WrappableTest, CallAsFunction) {
   EXPECT_EQ(0, object->result());
   v8::Handle<v8::String> source = StringToV8(isolate,
                                              "(function(obj) {"
-                                             "obj(42);"
+                                             "obj(42, 2, 5);"
                                              "})");
   gin::TryCatch try_catch;
   v8::Handle<v8::Script> script = v8::Script::Compile(source);
@@ -256,7 +256,7 @@ TEST_F(WrappableTest, CallAsConstructor) {
   EXPECT_EQ(0, object->result());
   v8::Handle<v8::String> source = StringToV8(isolate,
                                              "(function(obj) {"
-                                             "new obj(42);"
+                                             "new obj(42, 2, 5);"
                                              "})");
   gin::TryCatch try_catch;
   v8::Handle<v8::Script> script = v8::Script::Compile(source);