replace isDevMode()

Author: annieyw

src/cdk/tree/tree.ts

@@ -17,7 +17,6 @@ import {
   ElementRef,
   HostBinding,
   Input,
-  isDevMode,
   IterableChangeRecord,
   IterableDiffer,
   IterableDiffers,
@@ -397,7 +396,7 @@ function getParentNodeAriaLevel(nodeElement: HTMLElement): number {
     parent = parent.parentElement;
   }
   if (!parent) {
-    if (isDevMode()) {
+    if (typeof ngDevMode === 'undefined' || ngDevMode) {
       throw Error('Incorrect tree structure containing detached node.');
     } else {
       return -1;

tools/public_api_guard/cdk/tree.d.ts

@@ -24,8 +24,6 @@ export declare class CdkNestedTreeNode<T> extends CdkTreeNode<T> implements Afte
     protected _children: T[];
     protected _differs: IterableDiffers;
     protected _elementRef: ElementRef<HTMLElement>;
-    _expanded: boolean;
-    _role: "treeitem" | "group";
     protected _tree: CdkTree<T>;
     nodeOutlet: QueryList<CdkTreeNodeOutlet>;
     constructor(_elementRef: ElementRef<HTMLElement>, _tree: CdkTree<T>, _differs: IterableDiffers);