TypeScript 3.4 related fixes

src/apps/model-server-query/index.tsx

@@ -105,7 +105,7 @@ const state: State = {
     query: new Rx.BehaviorSubject(QueryList[1].definition),
     id: new Rx.BehaviorSubject('1cbs'),
     params: new Rx.BehaviorSubject({ }),
-    isBinary: new Rx.BehaviorSubject(false),
+    isBinary: new Rx.BehaviorSubject<boolean>(false),
     models: new Rx.BehaviorSubject<number[]>([]),
     url: new Rx.Subject()
 }

src/mol-util/param-definition.ts

@@ -168,7 +168,7 @@ export namespace ParamDefinition {
     }
 
     export interface NamedParams<T = any, K = string> { name: K, params: T }
-    export type NamedParamUnion<P extends Params, K = keyof P> = K extends any ? NamedParams<P[K]['defaultValue'], K> : never
+    export type NamedParamUnion<P extends Params, K extends keyof P = keyof P> = K extends any ? NamedParams<P[K]['defaultValue'], K> : never
     export interface Mapped<T extends NamedParams<any, any>> extends Base<T> {
         type: 'mapped',
         select: Select<string>,