Revert of Replace Release() { delete this; } in fde_xml_imp.h

Revert of Replace Release() { delete this; } in fde_xml_imp.h (patchset #7 id:120001 of https://codereview.chromium.org/1981003002/ )

Reason for revert:
Broke the ASAN Bot

Original issue's description:
> Replace Release() { delete this; } in fde_xml_imp.h
> 
> Committed: https://pdfium.googlesource.com/pdfium/+/fa34e805fd03ba81bcfe1148cf96b24fe63b39a0

TBR=tsepez@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

[Lei Zhang, 2016-05-16 22:57:18]

Created Revert of Replace Release() { delete this; } in fde_xml_imp.h

[commit-bot: I haz the power, 2016-05-16 22:57:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1980223002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1980223002/1

[commit-bot: I haz the power, 2016-05-16 22:57:30]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-05-16 22:57:31]

Failed to apply the patch.

[Tom Sepez, 2016-05-16 23:01:02]

On 2016/05/16 22:57:31, commit-bot: I haz the power wrote:
> Failed to apply the patch.

Beat you to it :).

[Tom Sepez, 2016-05-16 23:01:02]

On 2016/05/16 22:57:31, commit-bot: I haz the power wrote:
> Failed to apply the patch.

Beat you to it :).