Omit needless words: don't drop the first parameter name for failability initializers.

Swift SVN r31431

include/swift/Basic/StringExtras.h

@@ -291,13 +291,16 @@ StringRef omitNeedlessWords(StringRef name, StringRef typeName, NameRole role);
 /// \param returnsSelf Whether the result of the function is 'Self'
 /// (in Swift) or 'instancetype' (in Objective-C).
 ///
+/// \param failableInitializer Whether the result is a failable initializer.
+///
 /// \returns true if any words were omitted, false otherwise.
 bool omitNeedlessWords(StringRef &baseName,
                        MutableArrayRef<StringRef> argNames,
                        StringRef resultType,
                        StringRef contextType,
                        ArrayRef<StringRef> paramTypes,
-                       bool returnsSelf);
+                       bool returnsSelf,
+                       bool failableInitializer);
 }
 
 #endif // LLVM_SWIFT_BASIC_STRINGEXTRAS_HPP