RFR: 8146986: JDI: Signature lookups for unprepared classes can take a long time

[Egor Ushakov]

Hi all, please review the fix

it disables caching for types when signature is not provided as 
described in the bug (this is one of the proposed solutions in the bug).

https://bugs.openjdk.java.net/browse/JDK-8146986
http://cr.openjdk.java.net/~eushakov/8146986/webrev.00/

Thanks!

-- 
Egor Ushakov
Software Developer
JetBrains
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