update existing tests after banning move-only types in generics

A number of our existing tests put move-only types in optionals and
used them as arguments to generic type parameters. It turns out that
many of these appearances in the tests were not crucial for the test's
functionality itself.

The little coverage for force-unwrapping an Optional<moveOnly>
that was lost will be regained once we make these types sound.

I also tried to tidy up some of the tests with consistent naming for
operations on values, i.e., `consumeVal` and `borrowVal` functions.

Author: kavon

test/SILGen/moveonly_var.swift

@@ -5,13 +5,21 @@
 // Declarations //
 //////////////////
 
+class OrdinaryClass {}
+
+@_moveOnly
+public enum MaybeKlass {
+    case just(Klass)
+    case none
+}
+
 @_moveOnly
 public class Klass {
     var intField: Int
-    var klsField: Klass?
+    var klsField: OrdinaryClass // FIXME(104504239): this is suppose to be MaybeKlass, or better yet, Optional<Klass>
 
     init() {
-        klsField = Klass()
+        klsField = OrdinaryClass()
         intField = 5
     }
 }

test/SILOptimizer/move_only_checker_addressonly_fail.swift

@@ -1,4 +1,4 @@
-// RUN: %target-swift-frontend -enable-experimental-move-only -verify %s -parse-stdlib -emit-sil
+// RUN: %target-swift-frontend -enable-experimental-move-only -verify %s -emit-sil
 
 func useValue<T>(_ x: T) {}
 func consumeValue<T>(_ x: __owned T) {}

test/SILOptimizer/moveonly_addresschecker.sil

@@ -9,7 +9,7 @@ public class CopyableKlass {}
 @_moveOnly
 public class Klass {
     var intField: Int
-    var k: Klass?
+    var k: Klass
     init()
 }
 

test/SILOptimizer/moveonly_addresschecker_diagnostics.sil

@@ -20,7 +20,7 @@ public class CopyableKlass {}
 @_moveOnly
 public class Klass {
     var intField: Int
-    var k: Klass?
+    var k: Klass
     init()
 }