[ownership] Add an interior_pointer error test for open_existential_box.

I didn't find one in the file, so I added it.

Author: gottesmm

test/SIL/ownership-verifier/interior_pointer.sil

@@ -1,4 +1,4 @@
-// RUN: %target-sil-opt -sil-ownership-verifier-enable-testing -ownership-verifier-textual-error-dumper -enable-sil-verify-all=0 %s -o /dev/null 2>&1 | %FileCheck %s
+// RUN: %target-sil-opt -module-name Swift -sil-ownership-verifier-enable-testing -ownership-verifier-textual-error-dumper -enable-sil-verify-all=0 %s -o /dev/null 2>&1 | %FileCheck %s
 // REQUIRES: asserts
 
 sil_stage canonical
@@ -11,6 +11,10 @@ class KlassUser {
   var field: Klass
 }
 
+protocol Error {
+  var _code: Int { get }
+}
+
 sil @use_builtinnativeobject_inguaranteed : $@convention(thin) (@in_guaranteed Builtin.NativeObject) -> ()
 
 // CHECK-LABEL: Function: 'simple_error_ref_element_addr'
@@ -136,3 +140,21 @@ bb0(%0 : @owned $KlassUser, %0a : @guaranteed $Klass):
   %3 = load [copy] %result : $*Klass
   return %3 : $Klass
 }
+
+// CHECK-LABEL: Error#: 0. Begin Error in Function: 'open_existential_box_interior_pointer_error'
+// CHECK-NEXT: Found outside of lifetime use?!
+// CHECK-NEXT: Value:   %1 = begin_borrow %0 : $Error                   // users: %3, %2
+// CHECK-NEXT: Consuming User:   end_borrow %1 : $Error                          // id: %3
+// CHECK-NEXT: Non Consuming User:   %6 = apply %5<@opened("01234567-89AB-CDEF-0123-000000000000") Error>(%2) : $@convention(witness_method: Error) <τ_0_0 where τ_0_0 : Error> (@in_guaranteed τ_0_0) -> Int // type-defs: %2; user: %7
+// CHECK-NEXT: Block: bb0
+// CHECK: Error#: 0. End Error in Function: 'open_existential_box_interior_pointer_error'
+sil [ossa] @open_existential_box_interior_pointer_error : $@convention(thin) (@owned Error) -> Int {
+bb0(%0 : @owned $Error):
+  %1 = begin_borrow %0 : $Error
+  %2 = open_existential_box %1 : $Error to $*@opened("01234567-89AB-CDEF-0123-000000000000") Error
+  end_borrow %1 : $Error
+  destroy_value %0 : $Error
+  %m = witness_method $@opened("01234567-89AB-CDEF-0123-000000000000") Error, #Error._code!getter, %2 : $*@opened("01234567-89AB-CDEF-0123-000000000000") Error : $@convention(witness_method: Error) <Self: Error> (@in_guaranteed Self) -> Int
+  %result = apply %m<@opened("01234567-89AB-CDEF-0123-000000000000") Error>(%2) : $@convention(witness_method: Error) <Self: Error> (@in_guaranteed Self) -> Int
+  return %result : $Int
+}