Make sure we only send Suspend/Resume events when we *actually* suspend/resume. This is done via the Device `_beforeSuspend`/`_afterResume` methods, and those were called by the *input handlers*, not the PM logic; which means they would fire, while the PM logic could actually take a smarter decision and *not* do what the event just sent implied ;).
(i.e., sleep with a cover -> suspend + actual suspend, OK; but if you then resume with a button -> input assumes resume, but PM will actually suspend again!).
Existing design issue made more apparent by #9448 ;).
Also fixes/generalizes a few corner-cases related to screen_saver_lock handling (e.g., don't allow USBMS during a lock).
And deal with the fallout of the main change to the Kobo frontlight ramp behavior ;).
* Rejig frontlight warmth API to more closely match the existing API, and, hopefully, clarify some of its quirks, and reduce boilerplate and duplicate code in platform implementations.
* Tweak Kindle:setDateTime to prefer using the platform's custom script, as in interacts better with the stock UI. And make the fallbacks handle old busybox versions better.
* Add Kindle PW5 support ;).
* Add warmth support to the Kindle platform.
* Random TextBoxWidget cleanups: make sure we immediately free destroyed instances.
* FrontLightWidget: Refactor to make it slightly less obnoxious to grok and update; i.e., separate layout from update, and properly separate brightness from warmth handling. Move to simpler widgets instead of reinventing the wheel.
* TextBoxWidgets: Implement `setText` to match TextWidget's API, as some callers may be using the two interchangeably (i.e., Button).
* NaturalLightWidget: Make sure we pass a string to InputText
* InputText: Add debug guards to catch bad callers not passing strings ;).
move state change event to higher level function so it will be called after powerd.is_fl_on is updated.
makes _setIntensity redundant so get rid of it
obsoletes #6667
