Suppress Phan warnings about calling undeclared class methods

The DeletedShareAPIController and ShareAPIController helpers for room
shares are defined in Talk, so the classes do not exist when Talk is not
installed. Due to this when the object returned by "getRoomShareHelper"
is used Phan complains that the class is not declared.

This is not a problem, though, because when the class is not available
"getRoomShareHelper" throws an exception, which is then caught where
that method was called. Therefore now those warnings from Phan are
suppressed (it would be better to use "@phan-suppress-next-line"
instead, but it is not yet available in our Phan version).

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>