Reland of [ios] Implemented LoadHtml w/o using data:// URLs. (patchset #1 id:1 of https://codereview.chromium.org/2306053002/ )

Reason for revert:
False alert. This was not the root cause. Relanding. Sorry for the noise.

Original issue's description:
> Revert of [ios] Implemented LoadHtml w/o using data:// URLs. (patchset #4 id:60001 of https://codereview.chromium.org/2295053003/ )
>
> Reason for revert:
> Breaking iOS build.
>
> Original issue's description:
> > [ios] Implemented LoadHtml w/o using data:// URLs.
> >
> > This allows loading HTML and setting a specific URL (last part is needed
> > by suggestions tests, which currently use private API to set the URL).
> >
> > BUG=619687
> >
> > Committed: https://crrev.com/7d93683d73e6bb131651275c752a0792f2733410
> > Cr-Commit-Position: refs/heads/master@{#416151}
>
> TBR=jyquinn@chromium.org,eugenebut@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=619687
>
> Committed: https://crrev.com/e04917c2cced1a397c9f959f6f27a1b44e245899
> Cr-Commit-Position: refs/heads/master@{#416246}

TBR=jyquinn@chromium.org,eugenebut@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=619687

Review-Url: https://codereview.chromium.org/2309433002
Cr-Commit-Position: refs/heads/master@{#416251}
6 files changed