clang-format: Fix space in decltype-constexprs.

Before:
  static constexpr bool Bar = decltype(bar()) ::value;

After:
  static constexpr bool Bar = decltype(bar())::value;

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@189449 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 1cc4389..5002c9c 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -138,6 +138,7 @@
 TEST_F(FormatTest, NestedNameSpecifiers) {
   verifyFormat("vector< ::Type> v;");
   verifyFormat("::ns::SomeFunction(::ns::SomeOtherFunction())");
+  verifyFormat("static constexpr bool Bar = decltype(bar())::value;");
 }
 
 TEST_F(FormatTest, OnlyGeneratesNecessaryReplacements) {