Rearrange snackbar msgs to avoid overlapping each other

[rroyGit]

The overlapping is seen when user denies Camera Permission and clicks on "Detect Text." The snackbar with message "Tap to capture. Pinch/Stretch to zoom" overlaps with the snackbar's message "Access to the camera is needed for detection." As a result, user is unable to press "OK" to request permission again.

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[rroyGit]

I signed it!

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