refactor(ErrorObservable): remove needless type param from ErrorObser…

…vable.create()

BREAKING CHANGE - `ErrorObservable.create()` is no longer take type parameter
`T`. You don't have to pass it.

src/observable/ErrorObservable.ts

@@ -54,7 +54,7 @@ export class ErrorObservable extends Observable<any> {
    * @name throw
    * @owner Observable
    */
-  static create<T>(error: any, scheduler?: Scheduler) {
+  static create(error: any, scheduler?: Scheduler): ErrorObservable {
     return new ErrorObservable(error, scheduler);
   }