Remove __consuming from CodeCompletion

Set the UserInaccessible bit to remove __consuming from code
completion until we commit to a real keyword.

rdar://40828289

Author: CodaFi

include/swift/AST/Attr.def

@@ -226,6 +226,7 @@ SIMPLE_DECL_ATTR(objcMembers, ObjCMembers,
 CONTEXTUAL_SIMPLE_DECL_ATTR(__consuming, Consuming,
   OnFunc | OnAccessor |
   DeclModifier |
+  UserInaccessible |
   NotSerialized, 40)
 CONTEXTUAL_SIMPLE_DECL_ATTR(mutating, Mutating,
   OnFunc | OnAccessor |

lib/IDE/CodeCompletion.cpp

@@ -4845,6 +4845,11 @@ static void addDeclKeywords(CodeCompletionResultSink &Sink) {
       // Treat keywords that could be the start of a pattern specially.
       return;
     }
+    // FIXME: __consuming should not appear in CodeCompletion until it is
+    // finalized in a language proposal.
+    if (Name == "__consuming")
+      return;
+
     CodeCompletionResultBuilder Builder(
         Sink, CodeCompletionResult::ResultKind::Keyword,
         SemanticContextKind::None, {});

test/SourceKit/CodeComplete/complete_override.swift.response

@@ -1,14 +1,5 @@
 {
   key.results: [
-    {
-      key.kind: source.lang.swift.keyword,
-      key.name: "__consuming",
-      key.sourcetext: "__consuming",
-      key.description: "__consuming",
-      key.typename: "",
-      key.context: source.codecompletion.context.none,
-      key.num_bytes_to_erase: 0
-    },
     {
       key.kind: source.lang.swift.keyword,
       key.name: "associatedtype",