Revert "Fix Clang-tidy modernize-deprecated-headers warnings in remaining files; other minor fixes."

This reverts commit r265454 since it broke the build.  E.g.:

  http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-incremental_build/22413/

llvm-svn: 265459
diff --git a/llvm/unittests/Support/TimerTest.cpp b/llvm/unittests/Support/TimerTest.cpp
index 8f05b35..f556a3f 100644
--- a/llvm/unittests/Support/TimerTest.cpp
+++ b/llvm/unittests/Support/TimerTest.cpp
@@ -13,7 +13,7 @@
 #if LLVM_ON_WIN32
 #include <windows.h>
 #else
-#include <ctime>
+#include <time.h>
 #endif
 
 using namespace llvm;
@@ -62,4 +62,4 @@
   EXPECT_FALSE(T1.hasTriggered());
 }
 
-} // end anonymous namespace
+} // end anon namespace