Revert "Use namespaced CentralAuthSessionProvider"
Revert "Use namespaced CentralAuthSessionProvider"

This reverts commit 393aace62191387737b18593ba7179a514435a0e.

Reason for revert: namespacing reverted in I1d358d178a3999e82e7a25e17851c3cf60d7ddaa.

Change-Id: If4f7ddf51cbd63dc782e61b389b3f45effc13299

wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo