[SR-13340] Code completion: missing signature completion for unresolved member call in argument position expecting optional type.

[nathawes]

Previous ID	SR-13340
Radar	rdar://problem/66490100
Original Reporter	@nathawes
Type	Bug
Status	Resolved
Resolution	Done

Additional Detail from JIRA

Votes	0
Component/s	CodeCompletion
Labels	Bug, FoundByStressTester
Assignee	@theblixguy
Priority	Medium

md5: a526812008b0c6b2fc107b02b7e6fafa

Issue Description:

Reproducer with July 31st 5.3 snapshot:

struct Foo {
  static func system(blarg: Int) -> Foo {
    return Foo()
  }
}
func other(x: Foo?) {} // If this is not optional, it works.
other(x: .system(/*complete here*/)) // 'blarg:' not suggested here. 

[nathawes]

@swift-ci create

[theblixguy]

Fixed on master by #33292 @nathawes please verify using next available snapshot. Thank you!