lambda: Add support for invoke-interface for boxed innate lambdas

Lambda closures created with the 'create-lambda' instruction
(termed "innate lambdas") can be turned into an object with 'box-lambda'.

This CL enables support for those kinds of lambdas to work with
'invoke-interface' by generating a proxy class for the lambda.

Note: MIPS32/64 support not included.

Bug: 24618608
Bug: 25107649
Change-Id: Ic8f1bb66ebeaed4097e758a50becf1cff6ccaefb