This commit adds a new key that will allow users to enhance their
debugging experience in suspending contexts when using the IR backend.
After the key is enabled, the following things are changed:
1. All variables in a suspending context are spilled regardless their
liveness.
2. Their LVT records are not shrunk.
3. ACONST_NULL is not spilled to dead variables.
#KT-48678 In progress
(cherry picked from commit 38d97d0621)
Nikita Nazarov
2ab92bcb7e