Merge branch 'master' of github.com:UnityTech/UIWidgets into layout

Author: Yuncong Zhang

Runtime/editor/editor_window.cs

@@ -166,11 +166,9 @@ protected virtual TimeSpan getTime() {
 
         void updatePhysicalSize() {
             var size = this.queryWindowSize();
-            this._lastWindowWidth = size.x;
-            this._lastWindowHeight = size.y;
             this._physicalSize = new Size(
-                this._lastWindowWidth * this._devicePixelRatio,
-                this._lastWindowHeight * this._devicePixelRatio);
+                size.x * this._devicePixelRatio,
+                size.y * this._devicePixelRatio);
         }