tsan: fix build with COMPILER_RT_TSAN_DEBUG_OUTPUT

[dvyukov]

Summary

COMPILER_RT_TSAN_DEBUG_OUTPUT enables TSAN_COLLECT_STATS,
which changes layout of runtime structs (some structs contain
stats when the option is enabled).
It's not OK to build runtime with the define, but tests without it.
The error is detected by build_consistency_stats/nostats.
Fix this by defining TSAN_COLLECT_STATS for tests to match the runtime.

compiler-rt/lib/tsan/tests/CMakeLists.txt

 include_directories(../rtl)
 
 add_custom_target(TsanUnitTests)
 set_target_properties(TsanUnitTests PROPERTIES
   FOLDER "Compiler-RT Tests")
 
 set(TSAN_UNITTEST_CFLAGS
   ${COMPILER_RT_UNITTEST_CFLAGS}
   ${COMPILER_RT_GTEST_CFLAGS}
   -I${COMPILER_RT_SOURCE_DIR}/include
   -I${COMPILER_RT_SOURCE_DIR}/lib
   -I${COMPILER_RT_SOURCE_DIR}/lib/tsan/rtl
   -DGTEST_HAS_RTTI=0
   -fno-rtti
 )
 
+if(COMPILER_RT_TSAN_DEBUG_OUTPUT)
+  # Need to match these flags with the runtime.
+  list(APPEND TSAN_UNITTEST_CFLAGS -DTSAN_COLLECT_STATS=1
+                                   -DTSAN_DEBUG_OUTPUT=2)
+endif()
+
 set(TSAN_TEST_ARCH ${TSAN_SUPPORTED_ARCH})
 
 set(LINK_FLAGS ${COMPILER_RT_UNITTEST_LINK_FLAGS})
 foreach(lib ${SANITIZER_TEST_CXX_LIBRARIES})
   list(APPEND LINK_FLAGS -l${lib})
 endforeach()
 
 if(APPLE)