Supply X & Y deltas in the right order when creating new-style wheel events.

remoting/host/event_executor_mac.cc

Index: remoting/host/event_executor_mac.cc
diff --git a/remoting/host/event_executor_mac.cc b/remoting/host/event_executor_mac.cc
index f2dcec33c9a316b60a32bd0916f55f368d3cc8c4..fffc598c38870b59321738b31e7bcaedf91ff921 100644
--- a/remoting/host/event_executor_mac.cc
+++ b/remoting/host/event_executor_mac.cc
@@ -205,7 +205,7 @@ void EventExecutorMac::InjectMouseEvent(const MouseEvent& event) {
     int delta_y = static_cast<int>(event.wheel_delta_y());
     base::mac::ScopedCFTypeRef<CGEventRef> event(
         CGEventCreateScrollWheelEvent(
-            NULL, kCGScrollEventUnitPixel, 2, delta_x, delta_y));
+            NULL, kCGScrollEventUnitPixel, 2, delta_y, delta_x));
     if (event)
       CGEventPost(kCGHIDEventTap, event);
   } else if (event.has_wheel_offset_x() && event.has_wheel_offset_y()) {