Camera2: Fail gracefully if an exception occurs within a callback

[lytefast]

This change should prevent hard crashes when we can't load cameraview.

Before: app crashes if these exception occur
This occurred while I was testing out cameraview and then created an intent to load the camera. When the intent came back and onResume() was called (which then called cameraview.start() the sample app would hard crash.

This prevents a hard crash but still leaves the cameraview in a broken state.

Was tested using https://github.com/lytefast/flex-input + Google Pixel Phone:
0) disable the google pixel from the blacklist in CameraFragment#isBlacklistedDevice()

1. load app
2. hit (+) button
3. go to camera
4. hit the right button to open the camera app
5. capture picture

Result: app hard crashes
With change: picture is captured, cameraview is broken, but the app is still running correctly.

[lytefast]

#102 is a better solution.

[lytefast]

Mistook #102 as solving this issue. But it address another issue.