Brian Steinberg Senior TV EditorABC News named Cecilia Vega and Jonathan Karl to new senior roles in its Washington operations, naming Vega the Disney news unit’s chief White House correspondent and Karl its chief Washington correspondent, as well as a co-anchor of the Sunday public-affairs program “This Week.”In a memo to staffers Tuesday, ABC News President James Goldston also named Mary Bruce a senior White House correspondent and MaryAlice Parks a weekend White House correspondent.