Revert of bluetooth: Return false for IsPresent only when bluetooth is not supported (patchset #1 id:1 of https://codereview.chromium.org/2248033006/ )

Reason for revert:
device_unittests: BluetoothTest.ConstructDefaultAdapter is failing.

Original issue's description:
> bluetooth: Return false for IsPresent only when bluetooth is not supported
>
> BUG=633274
>
> Committed: https://crrev.com/784971913adcc32bdb22a92da6ac237a7de88a2b
> Cr-Commit-Position: refs/heads/master@{#413192}

TBR=jyasskin@chromium.org,ortuno@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=633274

Review-Url: https://codereview.chromium.org/2262033002
Cr-Commit-Position: refs/heads/master@{#413402}
1 file changed