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The main differences are:
- it uses AdbWrapper.Shell to actually execute the command.
- when the cmd is supplied as a list of a command and its arguments,
  the arguments are quoted to prevent them from being (mis)interpreted
  by the shell.
- a new single_line option to check that the output produces contains a single line, and return the value of that line.

BUG=267773

Review URL: https://codereview.chromium.org/659533002

Cr-Commit-Position: refs/heads/master@{#300237}