vim: fix rainbow activating when it shouldn't

vim/vimrc

@@ -175,6 +175,14 @@ fu _agw.set_color(scheme)
 	endif
 endfu
 
+fu _agw.set_rainbow()
+	if g:_agw.is_lang(&ft)
+		exec 'RainbowToggleOn'
+	else
+		exec 'RainbowToggleOff'
+	endif
+endfu
+
 " Settings -------------------------------------------------------------------|
 
 " general settings (use :help for these)
@@ -529,7 +537,7 @@ augroup AGW
 
 	" Enable rainbow braces
 	if _agw.use_rainbow != 0
-		au BufEnter * if _agw.is_lang(&ft) | exec 'RainbowToggleOn' | endif
+		au BufEnter * call _agw.set_rainbow()
 	endif
 
 	" suppress readonly warnings