Every function return should be an invalidation point for VMTraps

[Keith Miller]

We want this as an optimization for VMTraps where we have the following problem:

DFG code, A, calls 1000 unique functions (also in DFG) in a loop that each take a long time to run. We insert traps in each of the unique calls but they never fire because we return to A, which calls the next function. i.e.

A() {
B();
C();
D();
E();
...
}