Duplicative method cleanup (#6431)

app/stores/CommentsStore.ts

@@ -1,4 +1,3 @@
-import filter from "lodash/filter";
 import orderBy from "lodash/orderBy";
 import { action, computed } from "mobx";
 import Comment from "~/models/Comment";
@@ -18,8 +17,9 @@ export default class CommentsStore extends Store<Comment> {
    * @returns Array of comments
    */
   threadsInDocument(documentId: string): Comment[] {
-    return this.inDocument(documentId).filter(
-      (comment) => !comment.parentCommentId
+    return this.filter(
+      (comment: Comment) =>
+        comment.documentId === documentId && !comment.parentCommentId
     );
   }
 
@@ -30,26 +30,12 @@ export default class CommentsStore extends Store<Comment> {
    * @returns Array of comments
    */
   inThread(threadId: string): Comment[] {
-    return filter(
-      this.orderedData,
-      (comment) =>
+    return this.filter(
+      (comment: Comment) =>
         comment.parentCommentId === threadId || comment.id === threadId
     );
   }
 
-  /**
-   * Returns a list of comments in a document.
-   *
-   * @param documentId ID of the document to get comments for
-   * @returns Array of comments
-   */
-  inDocument(documentId: string): Comment[] {
-    return filter(
-      this.orderedData,
-      (comment) => comment.documentId === documentId
-    );
-  }
-
   @action
   setTyping({
     commentId,