[Managed Session] Revert login disclosure string to previous version

One of the new disclosure strings on the login screen was deemed a bit too strong on the words and was causing people to be distressed, therefore we are reverting it to the previous version.

Bug: 903810
Change-Id: I761b978fb553024bcfb2ac2efd7e208d513ee703
Reviewed-on: https://chromium-review.googlesource.com/c/1329781
Commit-Queue: Ivan Šandrk <isandrk@chromium.org>
Reviewed-by: Kush Sinha <sinhak@chromium.org>
Reviewed-by: Drew Wilson <atwilson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606902}

ash/ash_strings.grd

@@ -1462,7 +1462,7 @@ This file contains the strings for ash.
         Managed by <ph name="DOMAIN">$1<ex>yourdomain.com</ex></ph>
       </message>
       <message name="IDS_ASH_LOGIN_PUBLIC_ACCOUNT_MONITORING_WARNING" desc="Template for text shown in the public account user pod, informing the user that this is a public, managed account.">
-        The administrator of this device has access to all activity, including passwords and communications.
+        The device admin may monitor your browsing activity.
       </message>
       <message name="IDS_ASH_LOGIN_PUBLIC_ACCOUNT_SIGNOUT_REMINDER" desc="Text shown in the public account user pod, reminding the user to log out.">
         Your internet session will be cleared when you sign out. <ph name="LEARN_MORE">$1<ex>Learn more</ex></ph>