[code-reflection] RFR: Implement bitwise/shift assignment operations [v2]

[Hannes Greule]

> This change adds support for compound assignments for bitwise operations and shift operations. Tests are also enhanced to cover those cases.
> 
> As with already existing operations, input types `byte`, `char`,  `short` are not converted to `int`. Again, we have the special case of shift operations where the spec dictates unary promotion. That's why currently the rhs is promoted to `int` even in shift compound assignments.
> 
> The additional methods in `InvokableLeafOps` are needed in the current design.

Hannes Greule has updated the pull request incrementally with one additional commit since the last revision:

  Fix missed change from rebase

-------------

Changes:
  - all: https://git.openjdk.org/babylon/pull/77/files
  - new: https://git.openjdk.org/babylon/pull/77/files/f2830406..50e1cd81

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=77&range=01
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=77&range=00-01

  Stats: 6 lines in 1 file changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/babylon/pull/77.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/77/head:pull/77

PR: https://git.openjdk.org/babylon/pull/77