update_engine: Change Omaha request updater version format

- Remove the "version" attribute of <request>

- Change the value of the "updaterversion" attribute of <request> to be
  the pure version number (e.g. change "ChromeOSUpdateEngine-1.0.0.0" to
  "1.0.0.0")

- Add the "updater" attribute to <request>, the value of which is the
  name of the update client (e.g. "ChromeOSUpdateEngine")

BUG=chromium:928798
TEST=unittests
TEST=cros flashed and the omaha request was:
 <?xml version="1.0" encoding="UTF-8"?>
<request protocol="3.0" updater="ChromeOSUpdateEngine" updaterversion="0.1.0.0" installsource="ondemandupdate" ismachine="1">
    <os version="Indy" platform="Chrome OS" sp="11756.0.2019_02_13_1337_x86_64"></os>
    <app appid="{196C49C7-152F-499B-9C64-F5B8A89E43A4}" version="11756.0.2019_02_13_1337" track="stable-channel" lang="en-US" board="edgar" hardware_class="EDGAR TEST A-A 3472" delta_okay="true" fw_version="" ec_version="" installdate="4340" >
        <updatecheck></updatecheck>
        <event eventtype="54" eventresult="1" previousversion="11426.0.2018_12_20_1355"></event>
    </app>
</request>

Change-Id: I9b1d889fabb539ee64ebe2e4417592a6355dd940
Reviewed-on: https://chromium-review.googlesource.com/1470839
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>

0 files changed, 0 insertions, 0 deletions