Im on a stock HTC One with T-Mobile.
I tend to watch a few movies using Google Play Movies and TV.
3 times now i have had my HTC One power cycle after starting a movie or within the first 15 minutes of me starting a movie.
I have had no reboots using YouTube, Netflix or Hulu Plus. Its only been with Google Play Movies and TV.
FYI, this is also not happening a lot. Maybe 1 out of every 10 uses. So maybe twice a month.
However this weekend it caused the phone to reboot and get stuck on the HTC One logo screen. When it got stuck on the logo screen i got really concerned that it was messed up. Luckily holding the power button down for 30 seconds powered it off and then it booted normally.

Has anybody else had an issue with Chromecast and HTC One?