Some other Great Flag issues

[b2198]

Apart from the issues I mentioned in the targetting from inside multi-tile buildings, I found some other problems with the way great flags work:

1. Even though it's not an unprotected garrison, enemy units can target abilities on units inside them:
2. Even though it's not an unprotected garrison, hwachas' area damage targets units inside them, instead of the flag itself: (unrelated, but hwachas also seem to only target bottom-left tile of multi-tile buildings, similar to the petardier issue posted by phoenixffyrnig, so in this example, I targeted the top wall)
3. Construct Road, Construct Stone Road and Mend Road abilities to do nothing when targetting a great flag that has a unit inside it. Maybe it's using the great flag when checking if it's able to be cast and them casting it on the unit, instead of on the flag?

Edit: unlike the issues in targetting from inside multi-tile buildings, these do not work properly if the ability has the flag itself as a valid target:

Edit 2: Great Flag, not Warbanner, sorry.