OptionalclockClock used for timestamps. Default: Date.now.
OptionalinitialStarting theme: a fixture name, a full Theme, or null for no active theme. Default 'dark'.
OptionallatencyArtificial latency (ms) applied before each result. Default 0, which
responds synchronously inside handleMessage.
OptionalschedulerScheduler used for deferred pushes. Default: setTimeout.
OptionalseedSeed for deterministic ids and fixture ordering. Default 1.
Options for
createMockThemeService.Example