This reverts commit 8d07d3f6.

Fixes https://github.com/flutter/flutter/issues/10630

Our emulator detection was based on a simple heuristic that was
failing for the Samsung Galaxy S8. Any heuristic is flawed since
Android devices can report whatever they want to adb, but this
change attempts to tighten the detection by listing known models
(by their ro.hardware property). Again, these values could be
spoofed by emulator system images, but it's less likely to be
an issue than with our previous (and fall-back) heuristic.

Fixes #10203
Related: #10248