refactor: remove duplicate types and correct some TODOs (#10763)

Author: rafaelss95

src/cdk/table/table.ts

@@ -178,7 +178,7 @@ export class CdkTable<T> implements CollectionViewer, OnInit, AfterContentChecke
       this._switchDataSource(dataSource);
     }
   }
-  private _dataSource: DataSource<T> | Observable<T[]> | T[] | T[];
+  private _dataSource: DataSource<T> | Observable<T[]> | T[];
 
   // TODO(andrewseguin): Remove max value as the end index
   //   and instead calculate the view on init and scroll.

src/lib/icon/icon-registry.ts

@@ -544,7 +544,7 @@ export class MatIconRegistry {
       return inProgressFetch;
     }
 
-    // TODO(jelbourn): for some reason, the `finally` operator "loses" the generic type on the
+    // TODO(jelbourn): for some reason, the `finalize` operator "loses" the generic type on the
     // Observable. Figure out why and fix it.
     const req = this._httpClient.get(url, {responseType: 'text'}).pipe(
       finalize(() => this._inProgressUrlFetches.delete(url)),

src/lib/menu/menu-trigger.ts

@@ -52,11 +52,11 @@ export const MAT_MENU_SCROLL_STRATEGY =
       }
     });
 
-// TODO(andrewseguin): Remove the kebab versions in favor of camelCased attribute selectors
-
 /** Default top padding of the menu panel. */
 export const MENU_PANEL_TOP_PADDING = 8;
 
+// TODO(andrewseguin): Remove the kebab versions in favor of camelCased attribute selectors
+
 /**
  * This directive is intended to be used in conjunction with an mat-menu tag.  It is
  * responsible for toggling the display of the provided menu instance.