Fix build error

Define gui_mch_get_scrollbar_xpadding and gui_mch_get_scrollbar_ypadding.

src/MacVim/gui_macvim.m

@@ -1165,6 +1165,24 @@ gui_mch_set_scrollbar_pos(
 }
 
 
+    int
+gui_mch_get_scrollbar_xpadding(void)
+{
+    // TODO: Calculate the padding for adjust scrollbar position when the
+    // Window is maximized.
+    return 0;
+}
+
+
+    int
+gui_mch_get_scrollbar_ypadding(void)
+{
+    // TODO: Calculate the padding for adjust scrollbar position when the
+    // Window is maximized.
+    return 0;
+}
+
+
     void
 gui_mch_set_scrollbar_thumb(
 	scrollbar_T *sb,

src/proto/gui_macvim.pro

@@ -160,6 +160,10 @@ gui_mch_set_scrollbar_pos(
 	int y,
 	int w,
 	int h);
+    int
+gui_mch_get_scrollbar_xpadding(void);
+    int
+gui_mch_get_scrollbar_ypadding(void);
     void
 gui_mch_set_scrollbar_thumb(
 	scrollbar_T *sb,