RFR: JDK-8238838: spurious error message for compact constructors with throws clause

[Vicente Romero]

Hi,

Please review the fix for [1] at [2]. The fix is oriented at showing a 
friendlier error message in case a throws clause is declared in a 
compact constructor. We already issue an error for this case for 
canonical constructors so the same support could be expected for compact 
ones. I had to modify the arguments for a generic error message used for 
compact and canonical constructors as the error for canonical 
constructors is shown in Attr while the error for compact is shown in 
the parser. This is because the syntax for compact constructors doesn't 
expect anything between the constructor's name and its body. As at 
parser time there are no symbols in the ASTs I changed a parameter for 
the generic error message from `symbol` to `name`. This change has 
provoked that other error logging related to constructors had to be changed.

Thanks,
Vicente

[1] https://bugs.openjdk.java.net/browse/JDK-8238838
[2] http://cr.openjdk.java.net/~vromero/8238838/webrev.00/