Fix for SourceKit test after 6e8de44

Author: tanadeau

test/SourceKit/DocSupport/doc_clang_module.swift.response

@@ -5508,7 +5508,7 @@ var FooSubUnnamedEnumeratorA1: Int { get }
         key.doc.full_as_xml: "<Function><Name>insert(_:)</Name><USR>s:FesRxs9OptionSetxzwx7ElementrS_6insertFwxS0_T8insertedSb17memberAfterInsertwxS0__</USR><Declaration>mutating func insert(_ newMember: Self) -&gt; (inserted: Bool, memberAfterInsert: Self)</Declaration><Abstract><Para>Inserts the given element into the option set if it is not already a member.</Para></Abstract><Parameters><Parameter><Name>newMember</Name><Direction isExplicit=\"0\">in</Direction><Discussion><Para>The element to insert.</Para></Discussion></Parameter></Parameters><ResultDiscussion><Para><codeVoice>(true, newMember)</codeVoice> if <codeVoice>newMember</codeVoice> was not contained in <codeVoice>self</codeVoice>. Otherwise, returns <codeVoice>(false, oldMember)</codeVoice>, where <codeVoice>oldMember</codeVoice> is the member of the set equal to <codeVoice>newMember</codeVoice>.</Para></ResultDiscussion><Discussion><Para>For example:</Para><CodeListing language=\"swift\"><zCodeLineNumbered><![CDATA[let purchasePrice = 87.55]]></zCodeLineNumbered><zCodeLineNumbered></zCodeLineNumbered><zCodeLineNumbered><![CDATA[var freeOptions: ShippingOptions = [.standard, .priority]]]></zCodeLineNumbered><zCodeLineNumbered><![CDATA[if purchasePrice > 50 {]]></zCodeLineNumbered><zCodeLineNumbered><![CDATA[    freeOptions.insert(.secondDay)]]></zCodeLineNumbered><zCodeLineNumbered><![CDATA[}]]></zCodeLineNumbered><zCodeLineNumbered><![CDATA[print(freeOptions.contains(.secondDay))]]></zCodeLineNumbered><zCodeLineNumbered><![CDATA[// Prints \"true\"]]></zCodeLineNumbered><zCodeLineNumbered></zCodeLineNumbered></CodeListing></Discussion></Function>",
         key.offset: 1702,
         key.length: 84,
-        key.fully_annotated_decl: "<decl.function.method.instance><syntaxtype.keyword>mutating</syntaxtype.keyword> <syntaxtype.keyword>func</syntaxtype.keyword> <decl.name>insert</decl.name>(<decl.var.parameter><decl.var.parameter.argument_label>_</decl.var.parameter.argument_label> <decl.var.parameter.name>newMember</decl.var.parameter.name>: <decl.var.parameter.type><ref.generic_type_param usr=\"s:tPs9OptionSet4SelfMx\">Self</ref.generic_type_param></decl.var.parameter.type></decl.var.parameter>) -&gt; <decl.function.returntype><tuple>(<tuple.element><tuple.element.argument_label>inserted</tuple.element.argument_label>: <tuple.element.type><ref.struct usr=\"s:Sb\">Bool</ref.struct></tuple.element.type></tuple.element>, <tuple.element><tuple.element.argument_label>memberAfterInsert</tuple.element.argument_label>: <tuple.element.type><ref.generic_type_param usr=\"s:tPs9OptionSet4SelfMx\">Self</ref.generic_type_param></tuple.element.type></tuple.element>)</tuple></decl.function.returntype></decl.function.method.instance>",
+        key.fully_annotated_decl: "<decl.function.method.instance><syntaxtype.attribute.builtin><syntaxtype.attribute.name>@discardableResult</syntaxtype.attribute.name></syntaxtype.attribute.builtin> <syntaxtype.keyword>mutating</syntaxtype.keyword> <syntaxtype.keyword>func</syntaxtype.keyword> <decl.name>insert</decl.name>(<decl.var.parameter><decl.var.parameter.argument_label>_</decl.var.parameter.argument_label> <decl.var.parameter.name>newMember</decl.var.parameter.name>: <decl.var.parameter.type><ref.generic_type_param usr=\"s:tPs9OptionSet4SelfMx\">Self</ref.generic_type_param></decl.var.parameter.type></decl.var.parameter>) -&gt; <decl.function.returntype><tuple>(<tuple.element><tuple.element.argument_label>inserted</tuple.element.argument_label>: <tuple.element.type><ref.struct usr=\"s:Sb\">Bool</ref.struct></tuple.element.type></tuple.element>, <tuple.element><tuple.element.argument_label>memberAfterInsert</tuple.element.argument_label>: <tuple.element.type><ref.generic_type_param usr=\"s:tPs9OptionSet4SelfMx\">Self</ref.generic_type_param></tuple.element.type></tuple.element>)</tuple></decl.function.returntype></decl.function.method.instance>",
         key.entities: [
           {
             key.kind: source.lang.swift.decl.var.local,