FlxBitmapFont: remove background of XNA fonts (#2187)

Performing bmd.threshold() with bgColor32 is necessary to prevent the background color from appearing between letters when a FlxBitmapText using this font is scaled by a non-integer value

flixel/graphics/frames/FlxBitmapFont.hx

@@ -424,12 +424,8 @@ class FlxBitmapFont extends FlxFramesCollection
 		var frameRect = flashRect;
 		frame.frame.copyToFlash(frameRect);
 
-		#if flash
-		// TODO: fix this issue...
-		// for some reason this line causes app crash on targets other than flash...
 		var bgColor32:Int = bmd.getPixel32(Std.int(frame.frame.x), Std.int(frame.frame.y));
 		bmd.threshold(bmd, frameRect, point, "==", bgColor32, FlxColor.TRANSPARENT, FlxColor.WHITE, true);
-		#end
 
 		if (charBGColor != FlxColor.TRANSPARENT)
 		{
@@ -658,4 +654,4 @@ class FlxBitmapFont extends FlxFramesCollection
 		font.updateSourceHeight();
 		return font;
 	}
-}
+}