fix(module:auto-complete, mention, tree-select): update cdk overlay positioning strategy (#1761)

close #1756

Author: hsuanxyz

Diff for: components/auto-complete/nz-autocomplete-trigger.directive.ts

@@ -220,7 +220,11 @@ export class NzAutocompleteTriggerDirective implements ControlValueAccessor, OnD
       new ConnectionPositionPair({ originX: 'start', originY: 'bottom' }, { overlayX: 'start', overlayY: 'top' }),
       new ConnectionPositionPair({ originX: 'start', originY: 'top' }, { overlayX: 'start', overlayY: 'bottom' })
     ];
-    this.positionStrategy = this._overlay.position().flexibleConnectedTo(this.getConnectedElement()).withPositions(positions);
+    this.positionStrategy = this._overlay.position()
+    .flexibleConnectedTo(this.getConnectedElement())
+    .withPositions(positions)
+    .withFlexibleDimensions(false)
+    .withPush(false);
     return this.positionStrategy;
   }
 

Diff for: components/mention/mention.component.ts

@@ -334,7 +334,11 @@ export class NzMentionComponent implements OnDestroy, AfterContentInit {
       new ConnectionPositionPair({ originX: 'start', originY: 'bottom' }, { overlayX: 'start', overlayY: 'top' }),
       new ConnectionPositionPair({ originX: 'start', originY: 'top' }, { overlayX: 'start', overlayY: 'bottom' })
     ];
-    this.positionStrategy = this.overlay.position().flexibleConnectedTo(this.trigger.el).withPositions(positions).withLockedPosition(true);
+    this.positionStrategy = this.overlay.position()
+    .flexibleConnectedTo(this.trigger.el)
+    .withPositions(positions)
+    .withFlexibleDimensions(false)
+    .withPush(false);
     return this.positionStrategy;
   }
 

Diff for: components/tree-select/nz-tree-select.component.ts

@@ -270,7 +270,11 @@ export class NzTreeSelectComponent implements ControlValueAccessor, OnInit, Afte
       new ConnectionPositionPair({ originX: 'start', originY: 'bottom' }, { overlayX: 'start', overlayY: 'top' }),
       new ConnectionPositionPair({ originX: 'start', originY: 'top' }, { overlayX: 'start', overlayY: 'bottom' })
     ];
-    this.positionStrategy = this.overlay.position().flexibleConnectedTo(this.treeSelect).withPositions(positions).withLockedPosition(true);
+    this.positionStrategy = this.overlay.position()
+    .flexibleConnectedTo(this.treeSelect)
+    .withPositions(positions)
+    .withFlexibleDimensions(false)
+    .withPush(false);
     return this.positionStrategy;
   }