1127015 - Convert some enums to enum classes in js/src/jit

Status: NEW

(Core :: JavaScript Engine: JIT, defect, P5)

Description

[Jan de Mooij [:jandem]]

We have some enums that are used a lot (MIRType, FrameType etc) and with enum classes we get better type safety (no more implicit conversion to integer and for instance comparing a MIRType to a JSValueType will be a compile error).

They also no longer pollute the namespace with the enum values (although these enums use a prefix so it's not really an issue). So we'd just replace:

MIRType_Int32 -> MIRType::Int32
JitFrame_BaselineJS -> FrameType::BaselineJS
etc.