Add public keywords to the QueryPage base class

Add public keywords to the QueryPage base class

A lot more methods do not have visibility keywords. Some probably
should be private, a lot need to be protected, but all this will be
a breaking change. In this patch I'm focusing on methods that are
already used as public methods. The added public keyword is not a
breaking change because it's the default anyway.

Change-Id: I52e34209557b00f97a4e68250afbeb7647b64146