Earlier quoted context omitted.
"I just don't trust it to be around long enough to be an investment for me." Normally I would be inclined to agree with you given that this is Google, but the good news is that Flutter is open source. So even if Google discontinues internal development on it, it's likely that the community will continue it anyway.
Dart (the lang used in Flutter) already failed to gain traction in the web dev community and nobody seems to be maintaining it there.
Dart for web underlies Hummingbird, Google's Flutter-for-web effort that was also announced as a sneak peak alongside the Flutter 1.0 announcement, so Dart for web is very much alive and maintained at Google.