Add KeyCode.F{1…12}

Author: japgolly

src/main/scala/org/scalajs/dom/ext/Extensions.scala

@@ -152,6 +152,18 @@ object KeyCode {
  final val X = 88
  final val Y = 89
  final val Z = 90
+ final val F1 = 112
+ final val F2 = 113
+ final val F3 = 114
+ final val F4 = 115
+ final val F5 = 116
+ final val F6 = 117
+ final val F7 = 118
+ final val F8 = 119
+ final val F9 = 120
+ final val F10 = 121
+ final val F11 = 122
+ final val F12 = 123
 
  @deprecated("Use KeyCode.Backspace instead", "0.8.1") final val backspace = Backspace
  @deprecated("Use KeyCode.Tab instead", "0.8.1") final val tab = Tab