NFC: Add Sema test for lifetime dependence

Author: meg-gupta

test/Sema/implicit_lifetime_dependence.swift

@@ -2,10 +2,10 @@
 // REQUIRES: asserts
 
 struct BufferView : ~Escapable, ~Copyable {
-  let ptr: UnsafeRawBufferPointer
+  let ptr: UnsafeRawBufferPointer?
   let c: Int
   @_unsafeNonescapableResult
-  init(_ ptr: UnsafeRawBufferPointer, _ c: Int) {
+  init(_ ptr: UnsafeRawBufferPointer?, _ c: Int) {
     self.ptr = ptr
     self.c = c
   }
@@ -23,3 +23,8 @@ struct ImplicitInit3 : ~Escapable, ~Copyable { // expected-error{{cannot infer l
   let mbv1: BufferView
   let mbv2: BufferView
 }
+
+func foo() -> BufferView { // expected-error{{cannot infer lifetime dependence , no parameters found that are ~Escapable or Escapable with a borrowing ownership}}
+  return BufferView(nil, 0)
+}
+