[SR-2406] Print __attribute__((noescape)) in the generated header

[belkadan]

Previous ID	SR-2406
Radar	rdar://problem/22885266
Original Reporter	@belkadan
Type	Bug
Status	Resolved
Resolution	Done

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Bug, PrintAsObjC, StarterBug
Assignee	@belkadan
Priority	Medium

md5: 2514d7b6317734b9c741b4d583e99dfd

relates to:

• SR-2529 Keep attribute((noescape)) when importing Clang types
• SR-2520 Type alias is lost when applying @escaping-ness

Issue Description:

If a Swift method takes a non-escaping closure parameter, the generated header should include __attribute__((noescape)) on that parameter's type.

[jtbandes]

Am I correct in thinking that the attribute should only be printed when the type in question is the type of a function param? If so, do you think it makes sense to add another argument to print() indicating whether we are printing a function param?

[jtbandes]

Implementing in #4438