Performance improvements in invoke-polymorphic runtime support

Fineses the runtime support for invoke-polymorphic to improve
MethodHandle benchmark measurements by an average of 14%.

- Faster conversion checks for non-exact invokes.
- Avoid conversion checks for CallerTransformers and Transforms.
- Fast path for exact invokes avoiding conversion checks.
- Use cheaper constructs where possible.

Most of these changes are driven by simulation in callgrind.

Bug: 30550796
Test: m test-art-host
Change-Id: I38722b0d41db8e528f2730a826b1710b9fd1f6a9