In a standalone Clang build, default to building tests, like LLVM does

LLVM_INCLUDE_TESTS is set in the top-level LLVM CMakeLists, which is not being
executed when Clang is built in a separate directory.

llvm-svn: 197423
GitOrigin-RevId: f7d23ff1a6c66f228d3dde796d50096a47d3fcb5
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8db8a9a..8435654 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -46,6 +46,10 @@
   set(LLVM_MAIN_INCLUDE_DIR "${LLVM_MAIN_SRC_DIR}/include")
   set(LLVM_BINARY_DIR ${CMAKE_BINARY_DIR})
 
+  if (NOT DEFINED LLVM_INCLUDE_TESTS)
+    set(LLVM_INCLUDE_TESTS ON)
+  endif()
+
   set(CMAKE_INCLUDE_CURRENT_DIR ON)
   include_directories("${PATH_TO_LLVM_BUILD}/include" "${LLVM_MAIN_INCLUDE_DIR}")
   link_directories("${PATH_TO_LLVM_BUILD}/lib")