BMenu: made left side padding font size relative.

* Also changed BMenuItem to make better use of that size.

src/kits/interface/Menu.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright 2001-2013 Haiku, Inc. All rights reserved.
+ * Copyright 2001-2015 Haiku, Inc. All rights reserved.
  * Distributed under the terms of the MIT license.
  *
  * Authors:
@@ -216,7 +216,7 @@ BMenu::BMenu(const char* name, menu_layout layout)
 	:
 	BView(BRect(0, 0, 0, 0), name, 0, B_WILL_DRAW),
 	fChosenItem(NULL),
-	fPad(14.0f, 2.0f, 20.0f, 0.0f),
+	fPad(std::max(14.0f, be_plain_font->Size() + 2.0f), 2.0f, 20.0f, 0.0f),
 	fSelected(NULL),
 	fCachedMenuWindow(NULL),
 	fSuper(NULL),