RFR(XS): 8191442: Regression in LambdaFormBuffer.replaceFunctions

[Claes Redestad]

Hi,

in JDK-8184777, we accidentally changed behavior of replaceFunctions 
from testing
identity to testing equality, causing a small startup regression on some 
sensitive
benchmarks in the process[1].

Patch to salvage the recently orphaned helper function:

http://cr.openjdk.java.net/~redestad/8191442/open.00/

Thanks!

/Claes

[1] Made worse by https://bugs.openjdk.java.net/browse/JDK-8191418