fix conflict between drag & scroll

Runtime/editor/editor_window.cs

@@ -15,10 +15,33 @@ namespace Unity.UIWidgets.editor {
 #if UNITY_EDITOR
     public abstract class UIWidgetsEditorWindow : EditorWindow, WindowHost {
         WindowAdapter _windowAdapter;
-
+
+        static readonly List<UIWidgetsEditorWindow> _activeEditorWindows = new List<UIWidgetsEditorWindow>();
+
+        [InitializeOnLoadMethod]
+        static void _OnBaseEditorWindowLoaded()
+        {
+            EditorApplication.quitting += () =>
+            {
+                foreach (var editorWindow in _activeEditorWindows) {
+                    editorWindow.OnDisable();
+                }
+
+                _activeEditorWindows.Clear();
+            };
+        }
+
         public UIWidgetsEditorWindow() {
             this.wantsMouseMove = true;
             this.wantsMouseEnterLeaveWindow = true;
+
+            _activeEditorWindows.Add(this);
+        }
+
+        void OnDestroy() {
+            if (_activeEditorWindows.Contains(this)) {
+                _activeEditorWindows.Remove(this);
+            }
         }
 
         protected virtual void OnEnable() {
@@ -404,7 +427,7 @@ void _doOnGUI(Event evt) {
                         -evt.delta.y * this._devicePixelRatio,
                         evt.mousePosition.x * this._devicePixelRatio,
                         evt.mousePosition.y * this._devicePixelRatio,
-                        InputUtils.getMouseButtonKey(evt.button)
+                        InputUtils.getScrollButtonKey()
                     );
                 }
                 else if (evt.type == EventType.DragUpdated) {

Runtime/gestures/binding.cs

@@ -109,6 +109,9 @@ evt is PointerDragFromEditorReleaseEvent
 
         void _handlePointerScrollEvent(PointerEvent evt) {
             this.pointerRouter.clearScrollRoute(evt.pointer);
+            if (!this.pointerRouter.acceptScroll()) {
+                return;
+            }
 
             HitTestResult result = new HitTestResult();
             this.hitTest(result, evt.position);

Runtime/gestures/pointer_router.cs

@@ -25,6 +25,10 @@ public void removeRoute(int pointer, PointerRoute route) {
                 this._routeMap.Remove(pointer);
             }
         }
+
+        public bool acceptScroll() {
+            return this._routeMap.Count == 0;
+        }
 
         public void clearScrollRoute(int pointer) {
             if (this._routeMap.ContainsKey(pointer)) {

Runtime/service/text_input.cs

@@ -345,6 +345,9 @@ public TextEditingValue compose(string composeText) {
             D.assert(!string.IsNullOrEmpty(composeText));
             var composeStart = this.composing == TextRange.empty ? this.selection.start : this.composing.start;
             var lastComposeEnd = this.composing == TextRange.empty ? this.selection.end : this.composing.end;
+
+            composeStart = Mathf.Clamp(composeStart, 0, this.text.Length);
+            lastComposeEnd = Mathf.Clamp(lastComposeEnd, 0, this.text.Length);
             var newText = this.text.Substring(0, composeStart) + composeText + this.text.Substring(lastComposeEnd);
             var componseEnd = composeStart + composeText.Length;
             return new TextEditingValue(