PlatformConfiguration does not contain brieflyShowPassword or nativeSpellCheckServiceDefined, and therefore PlatformDispatcher's properties of the same name are not backed by the config.

Use case

I was working on cleaning up the TestPlatformDispatcher by having all of the test properties backed by the config and found that these two properties were inconsistent with the rest of the properties for PlatformDispatcher in that they were not backed by the config.

Proposal

Add these two properties to PlatformConfiguration, and update PlatformDispatcher's matching properties to be backed by the config.