fix editor mouse button key

Runtime/editor/editor_window.cs

 using System;
 using System.Collections.Generic;
 using Unity.UIWidgets.async;
+using Unity.UIWidgets.engine;
 using Unity.UIWidgets.foundation;
 using Unity.UIWidgets.rendering;
 using Unity.UIWidgets.scheduler;
                         timeStamp: Timer.timespanSinceStartup,
                         change: PointerChange.down,
                         kind: PointerDeviceKind.mouse,
-                        device: evt.button,
+                        device: InputUtils.getMouseButtonKey(evt.button),
                         physicalX: evt.mousePosition.x * this._devicePixelRatio,
                         physicalY: evt.mousePosition.y * this._devicePixelRatio
                     );
                         timeStamp: Timer.timespanSinceStartup,
                         change: PointerChange.up,
                         kind: PointerDeviceKind.mouse,
-                        device: evt.button,
+                        device: InputUtils.getMouseButtonKey(evt.button),
                         physicalX: evt.mousePosition.x * this._devicePixelRatio,
                         physicalY: evt.mousePosition.y * this._devicePixelRatio
                     );
                         timeStamp: Timer.timespanSinceStartup,
                         change: PointerChange.move,
                         kind: PointerDeviceKind.mouse,
-                        device: evt.button,
+                        device: InputUtils.getMouseButtonKey(evt.button),
                         physicalX: evt.mousePosition.x * this._devicePixelRatio,
                         physicalY: evt.mousePosition.y * this._devicePixelRatio
                     );
                         timeStamp: Timer.timespanSinceStartup,
                         change: PointerChange.hover,
                         kind: PointerDeviceKind.mouse,
-                        device: evt.button,
+                        device: InputUtils.getMouseButtonKey(evt.button),
                         physicalX: evt.mousePosition.x * this._devicePixelRatio,
                         physicalY: evt.mousePosition.y * this._devicePixelRatio
                     );
                         -evt.delta.y * this._devicePixelRatio,
                         evt.mousePosition.x * this._devicePixelRatio,
                         evt.mousePosition.y * this._devicePixelRatio,
-                        evt.button
+                        InputUtils.getMouseButtonKey(evt.button)
                     );
                 }
                 else if (evt.type == EventType.DragUpdated) {
                         kind: PointerDeviceKind.mouse,
-                        device: evt.button,
+                        device: InputUtils.getMouseButtonKey(evt.button),
                         physicalX: evt.mousePosition.x * this._devicePixelRatio,
                         physicalY: evt.mousePosition.y * this._devicePixelRatio
                     );
                         timeStamp: Timer.timespanSinceStartup,
                         change: PointerChange.dragFromEditorRelease,
                         kind: PointerDeviceKind.mouse,
-                        device: evt.button,
+                        device: InputUtils.getMouseButtonKey(evt.button),
                         physicalX: evt.mousePosition.x * this._devicePixelRatio,
                         physicalY: evt.mousePosition.y * this._devicePixelRatio
                     );