[DIAL] (1st) Added SafeDialAppInfoParser class to parse DIAL app info XML

Recent changes removed dial_device_description_parser_impl* from
chrome/utility/media_router and introduces a new SafeXmlParser.
(https://chromium-review.googlesource.com/c/chromium/src/+/770920)

Abandoned previous DialAppInfoParser patch
(https://chromium-review.googlesource.com/c/chromium/src/+/745538),
resolved most comments in the new patch and added a SafeDialAppInfoParser
class which uses SafeXmlParser.

Bug: 779892
Change-Id: I1c0d141381e1a8c992888476e8643385a96db06f
Reviewed-on: https://chromium-review.googlesource.com/826126


Reviewed-by: Jay Civelli <jcivelli@chromium.org>
Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: Derek Cheng <imcheng@chromium.org>
Commit-Queue: Bin Zhao <zhaobin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524412}