clang-format: Fix incorrect lambda recognition.

Before:
  std::unique_ptr<int[]> foo() {}

After:
  std::unique_ptr<int []> foo() {}

Also, the formatting could go severely wrong after such a function
before.

llvm-svn: 199817
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index a029176..7b3ea6e 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -7889,6 +7889,7 @@
   verifyFormat("constexpr char hello[]{ \"hello\" };");
   verifyFormat("double &operator[](int i) { return 0; }\n"
                "int i;");
+  verifyFormat("std::unique_ptr<int[]> foo() {}");
 }
 
 TEST_F(FormatTest, FormatsBlocks) {