Adobe makes money from its Flash editing tools, so they probably do not care if Flash is replaced with HTML5 as long as their editing tools for HTML5 become the standard. In fact, Adobe may even be relieved that it looks like they may be able to drop Flash as a primary platform soon, because they obviously have difficult maintaining the plugin.

There's still an opening for Adobe to make themselves the standard HTML5 IDE (as they are the standard photography "IDE") and still reap as much money as they were making from Flash, but without the overhead of maintaining the runtime.