Compiler should optimize common boolean return patterns

Version Used: Rosyln master branch from 2nd April 2019

Steps to Reproduce: [Sharplab Demo]

1. Have this code: public bool Proper(object o) { return o is object; }
2. Also, have this unoptimized version public bool ShouldBeOptimized(object o) { if (o is object) { return true; } return false; }

Expected Behavior: Identical IL output, as they are semantically identical. This wouldn't be an issue but it does affect JIT output seemingly (JIT64 desktop, tested on Sharplab above) - it switches a setcc ; movzx pattern to a full branch, which is not ideal

Actual Behavior: IL generation has an additional branch and changes the generated JIT

It is a very minor issue but was recommended to create an issue for it