Summary:
This diff adds a set of access paths holding a value returned from a method annotated with Functional to the domain.
If a "functional" value is written to a field, we won't count that right as an unprotected access.
The idea is to be able to use the Functional annotation to get rid of benign race false positive, such as:
```
Functional T iAlwaysReturnTheSameThing();
T mCache;
T memoizedGetter() {
if (mCache == null) {
mCache = iAlwaysReturnTheSameThing();
}
return mCache;
}
```
Although there is a write-write race on `mCache`, we don't care because it will be assigned to the same value regardless of which writer wins.
Reviewed By: peterogithub
Differential Revision: D4476492
fbshipit-source-id: cfa5dfc
Sam Blackshear