Add mouse wheel horizontal scroll support

jsonrpc.go

@@ -994,7 +994,7 @@ var rpcHandlers = map[string]RPCHandler{
 	"keyboardReport":         {Func: rpcKeyboardReport, Params: []string{"modifier", "keys"}},
 	"absMouseReport":         {Func: rpcAbsMouseReport, Params: []string{"x", "y", "buttons"}},
 	"relMouseReport":         {Func: rpcRelMouseReport, Params: []string{"dx", "dy", "buttons"}},
-	"wheelReport":            {Func: rpcWheelReport, Params: []string{"wheelY"}},
+	"wheelReport":            {Func: rpcWheelReport, Params: []string{"wheelY", "wheelX"}},
 	"getVideoState":          {Func: rpcGetVideoState},
 	"getUSBState":            {Func: rpcGetUSBState},
 	"unmountImage":           {Func: rpcUnmountImage},

usb.go

@@ -38,8 +38,8 @@ func rpcRelMouseReport(dx, dy int8, buttons uint8) error {
 	return gadget.RelMouseReport(dx, dy, buttons)
 }
 
-func rpcWheelReport(wheelY int8) error {
-	return gadget.AbsMouseWheelReport(wheelY)
+func rpcWheelReport(wheelY, wheelX int8) error {
+	return gadget.AbsMouseWheelReport(wheelY, wheelX)
 }
 
 var usbState = "unknown"