[clang-format] Move comment tests to their own file.

Summary: With a growing suite of comment-related tests, it makes sense to take them out of the main test file. No functional changes.

Reviewers: djasper

Reviewed By: djasper

Subscribers: cfe-commits, klimek, mgorny

Differential Revision: https://reviews.llvm.org/D29713

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@294439 91177308-0d34-0410-b5e6-96231b3b80d8

unittests/Format/CMakeLists.txt

@@ -5,6 +5,7 @@ set(LLVM_LINK_COMPONENTS
 add_clang_unittest(FormatTests
   CleanupTest.cpp
   FormatTest.cpp
+  FormatTestComments.cpp
   FormatTestJava.cpp
   FormatTestJS.cpp
   FormatTestObjC.cpp