[clang-format] Handle unary operator overload with arguments and specifiers

Before:
  int operator++(int)noexcept;

After:
  int operator++(int) noexcept;

Patch by Igor Sugak. Thank you!

llvm-svn: 317473
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 82530c0..c61a569 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -5591,6 +5591,7 @@
   verifyFormat("bool operator!=();");
   verifyFormat("int operator+();");
   verifyFormat("int operator++();");
+  verifyFormat("int operator++(int) volatile noexcept;");
   verifyFormat("bool operator,();");
   verifyFormat("bool operator();");
   verifyFormat("bool operator()();");