Update tests after pulling fix from master

Author: calda

Diff for: lib/Sema/MiscDiagnostics.cpp

@@ -1882,7 +1882,9 @@ class ImplicitSelfUsageChecker : public BaseDiagnosticWalker {
     }
 
     // If the self decl refers to a weak capture, then implicit self is not
-    // allowed. Self must me unwrapped in a weak self closure.
+    // allowed. Self must be unwrapped in a `guard let self` / `if let self`
+    // condition first. This is usually enforced by the type checker, but
+    // isn't in some cases (e.g. when calling a method on `Optional<Self>`).
     //  - When validating implicit self usage in a nested closure, it's not
     //    necessary for self to be unwrapped in this parent closure. If self
     //    isn't unwrapped correctly in the nested closure, we would have

Diff for: test/expr/closure/closures_swift6.swift

@@ -501,14 +501,14 @@ class TestGithubIssue70089 {
       }
 
       doVoidStuff { [weak self] in
-        doVoidStuff { [self] in // expected-error {{value of optional type 'TestGithubIssue70089?' must be unwrapped to a value of type 'TestGithubIssue70089'}} expected-note {{coalesce using '??' to provide a default when the optional value contains 'nil'}} expected-note {{force-unwrap using '!' to abort execution if the optional value contains 'nil'}}
-          x += 1
+        doVoidStuff { [self] in
+          x += 1 // expected-error {{explicit use of 'self' is required when 'self' is optional, to make control flow explicit}} expected-note{{reference 'self?.' explicitly}}
         }
       }
 
       doVoidStuff { [weak self] in
-        doVoidStuff { [self] in // expected-error {{value of optional type 'TestGithubIssue70089?' must be unwrapped to a value of type 'TestGithubIssue70089'}} expected-note {{coalesce using '??' to provide a default when the optional value contains 'nil'}} expected-note {{force-unwrap using '!' to abort execution if the optional value contains 'nil'}}
-          self.x += 1
+        doVoidStuff { [self] in
+          self.x += 1 // expected-error {{value of optional type 'TestGithubIssue70089?' must be unwrapped to refer to member 'x' of wrapped base type 'TestGithubIssue70089'}} expected-note {{chain the optional using '?' to access member 'x' only for non-'nil' base values}} expected-note{{force-unwrap using '!' to abort execution if the optional value contains 'nil'}} 
         }
       }
 
@@ -647,12 +647,6 @@ class TestGithubIssue69911 {
           }
         }
       }
-
-      doVoidStuff { [weak self] in
-        doVoidStuff { [self] in // expected-error {{value of optional type 'TestGithubIssue69911?' must be unwrapped to a value of type 'TestGithubIssue69911'}} expected-note{{coalesce using '??' to provide a default when the optional value contains 'nil'}} expected-note{{force-unwrap using '!' to abort execution if the optional value contains 'nil'}}
-          x += 1
-        }
-      }
     }
 }