As Flash won't be supported anymore cross-platform, many sites will rescript to HTML5. Of course, smaller websites that just do not have available the resources needed for that effort will keep running on Flash, but the more relevant ones will go over rather sooner than later (the more content and complexity is added, the harder the transition gets). I'd wager that indeed the Flash Player will be available in the Play Store for some time to come, but why you'd want to use it (given the security issues that even Adobe herself has admitted often enough) AFTER the major players have transscripted is slightly beyond me.
(It's only in use on porn sites nowadays, it seems. Not that I ever visit any. I've heard that through the grapevine...
"Professionals are predictable, but the world is full of amateurs."
-- Murphy's Military Laws, as referenced on http://www.military-info.com/freebies/murphy.htm
"The skill of accurate perception is called cynicism by those who don't possess it."
-- Alan Millar