Remove widget support for CallViewHeader

src/components/views/voip/PictureInPictureDragger.tsx

@@ -13,6 +13,7 @@ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */
+
 import React, { createRef } from 'react';
 import UIStore from '../../../stores/UIStore';
 import { IApp } from '../../../stores/WidgetStore';