RFR 8187359: JShell: Give comprehensible error when user method name matches Object method

[Robert Field]

Thanks Jan!

Coming back to this, post repo consolidation, I see this is 
unnecessarily restrictive, the error occurs only when the signatures 
match as well.   Ideally we want users to never see this error, so 
making it less common is good.  I've changed the new error to only 
appear when it would have failed (with a confusing error).  Now methods 
like:

     boolean equals(foo f1, Foo f2) ...

would be allowed.

The code remains the same in concept but is distributed differently -- 
switching out diagnostics after compilation.

And a corresponding update and additions to the tests.

Updated webrev:

      http://cr.openjdk.java.net/~rfield/8187359v3.webrev/

-Robert

On 09/12/17 12:50, Jan Lahoda wrote:
> Seems OK.
>
> Jan
>
> On 8.9.2017 07:38, Robert Field wrote:
>> Please review.
>>
>> Bug:
>>
>>      https://bugs.openjdk.java.net/browse/JDK-8187359
>>
>> Webrev:
>>
>>      http://cr.openjdk.java.net/~rfield/8187359v0.webrev/
>>
>> Thanks,
>> Robert
>>