[cleanup] Remove unnecessary code

This code is obsolete with the current typings

Bug: none
Change-Id: I91d93df5a8053442af5c306abba7efaa9a1074d9
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6276554
Auto-Submit: Nikolay Vitkov <[email protected]>
Commit-Queue: Alex Rudenko <[email protected]>
Commit-Queue: Nikolay Vitkov <[email protected]>
Reviewed-by: Alex Rudenko <[email protected]>

Author: Lightning00Blade

front_end/core/sdk/CSSModel.ts

@@ -368,7 +368,7 @@ export class CSSModel extends SDKModel<EventTypes> {
 
     const payload = {
       cssModel: this,
-      node: (node as DOMNode),
+      node,
       inlinePayload: matchedStylesResponse.inlineStyle || null,
       attributesPayload: matchedStylesResponse.attributesStyle || null,
       matchedPayload: matchedStylesResponse.matchedCSSRules || [],

front_end/core/sdk/DOMModel.ts

@@ -1268,7 +1268,7 @@ export class DOMModel extends SDKModel<EventTypes> {
   async pushNodeToFrontend(objectId: Protocol.Runtime.RemoteObjectId): Promise<DOMNode|null> {
     await this.requestDocument();
     const {nodeId} = await this.agent.invoke_requestNode({objectId});
-    return nodeId ? this.nodeForId(nodeId) : null;
+    return this.nodeForId(nodeId);
   }
 
   pushNodeByPathToFrontend(path: string): Promise<Protocol.DOM.NodeId|null> {

front_end/panels/elements/ElementsPanel.ts

@@ -617,7 +617,7 @@ export class ElementsPanel extends UI.Panel.Panel implements UI.SearchableView.S
       if (savedSelectedNodeOnReset !== this.selectedNodeOnReset) {
         return;
       }
-      let node: (SDK.DOMModel.DOMNode|null) = restoredNodeId ? domModel.nodeForId(restoredNodeId) : null;
+      let node = domModel.nodeForId(restoredNodeId);
       if (!node) {
         const inspectedDocument = domModel.existingDocument();
         node = inspectedDocument ? inspectedDocument.body || inspectedDocument.documentElement : null;