fix(tree): fixed tests and removed redundant code

Author: tishko0

projects/igniteui-angular/src/lib/tree/tree-navigation.spec.ts

@@ -10,6 +10,7 @@ import { IgxTreeService } from './tree.service';
 import { IgxTreeComponent } from './tree.component';
 import { IgxTree, IgxTreeNode, IgxTreeSelectionType } from './common';
 import { IgxTreeNodeComponent } from './tree-node/tree-node.component';
+import { PlatformUtil } from '../core/utils';
 
 describe('IgxTree - Navigation #treeView', () => {
 
@@ -780,7 +781,8 @@ describe('IgxTree - Navigation #treeView', () => {
                 spyOn(nav, 'update_disabled_cache');
                 spyOn(nav, 'update_visible_cache');
                 spyOn(nav, 'register');
-                const tree = new IgxTreeComponent(nav, mockSelectionService, mockTreeService, mockElementRef);
+                const mockPlatform = jasmine.createSpyObj('platform', ['isBrowser', 'isServer']);
+                const tree = new IgxTreeComponent(nav, mockSelectionService, mockTreeService, mockElementRef, mockPlatform);
                 tree.nodes = mockQuery;
                 expect(nav.register).toHaveBeenCalledWith(tree);
                 expect(nav.init_invisible_cache).not.toHaveBeenCalled();

projects/igniteui-angular/src/lib/tree/tree-selection.spec.ts

@@ -552,7 +552,9 @@ describe('IgxTree - Selection #treeView', () => {
         const selectionService = new IgxTreeSelectionService();
         const treeService = new IgxTreeService();
         const navService = new IgxTreeNavigationService(treeService, selectionService);
-        const tree = new IgxTreeComponent(navService, selectionService, treeService, null);
+        const mockPlatform = jasmine.createSpyObj('platform', ['isBrowser', 'isServer']);
+        mockPlatform.isBrowser = true;
+        const tree = new IgxTreeComponent(navService, selectionService, treeService, null, mockPlatform);
 
         beforeEach(() => {
             mockNodes = TreeTestFunctions.createNodeSpies(0, 5);

projects/igniteui-angular/src/lib/tree/tree.component.ts

@@ -504,6 +504,11 @@ export class IgxTreeComponent implements IgxTree, OnInit, AfterViewInit, OnDestr
         requestAnimationFrame(() => {
             this.selectionService.selectNodesWithNoEvent(toBeSelected);
         });
+        if(this.platform.isBrowser) {
+            requestAnimationFrame(() => {
+                this.selectionService.selectNodesWithNoEvent(toBeSelected);
+            });
+        }
         this.forceSelect = [];
         this.nodes.forEach(node => {
             node.expandedChange.pipe(takeUntil(this.unsubChildren$)).subscribe(nodeState => {

projects/igniteui-angular/src/lib/tree/tree.spec.ts

@@ -11,6 +11,7 @@ import { IgxTreeNodeComponent } from './tree-node/tree-node.component';
 import { IgxTreeSelectionService } from './tree-selection.service';
 import { IgxTreeComponent } from './tree.component';
 import { IgxTreeService } from './tree.service';
+import { PlatformUtil } from '../core/utils';
 
 const TREE_ROOT_CLASS = 'igx-tree__root';
 const NODE_TAG = 'igx-tree-node';
@@ -45,8 +46,10 @@ describe('IgxTree #treeView', () => {
             mockElementRef = jasmine.createSpyObj('elementRef', [], {
                 nativeElement: document.createElement('div')
             });
+            const mockPlatform = jasmine.createSpyObj('platform', ['isBrowser', 'isServer']);
+            mockPlatform.isBrowser = true;
             tree?.ngOnDestroy();
-            tree = new IgxTreeComponent(mockNavService, mockSelectionService, mockTreeService, mockElementRef);
+            tree = new IgxTreeComponent(mockNavService, mockSelectionService, mockTreeService, mockElementRef, mockPlatform);
             mockNodes = jasmine.createSpyObj('mockList', ['toArray'], {
                 changes: new Subject<void>(),
                 get first() {