Revert of Add GN targets for samples (patchset #1 id:1 of https://codereview.chromium.org/1955723003/ )

Reason for revert:
Blocks roll: https://codereview.chromium.org/1956223002/

Original issue's description:
> Add GN targets for samples
>
> BUG=chromium:609107
> R=machenbach@chromium.org
> LOG=n
>
> Committed: https://crrev.com/19a8e09cc0bafa5071c52243234bfc8512210065
> Cr-Commit-Position: refs/heads/master@{#36072}

TBR=machenbach@chromium.org,jochen@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:609107
LOG=n

Review-Url: https://codereview.chromium.org/1955353002
Cr-Commit-Position: refs/heads/master@{#36096}