Cleans up macro definitions.

test/gtest-port_test.cc

@@ -40,9 +40,9 @@
 // included, or there will be a compiler error.  This trick is to
 // prevent a user from accidentally including gtest-internal-inl.h in
 // his code.
-#define GTEST_IMPLEMENTATION
+#define GTEST_IMPLEMENTATION_ 1
 #include "src/gtest-internal-inl.h"
-#undef GTEST_IMPLEMENTATION
+#undef GTEST_IMPLEMENTATION_
 
 namespace testing {
 namespace internal {
@@ -76,7 +76,7 @@ TEST(GtestCheckSyntaxTest, WorksWithSwitch) {
       GTEST_CHECK_(true) << "Check failed in switch case";
 }
 
-#ifdef GTEST_HAS_DEATH_TEST
+#if GTEST_HAS_DEATH_TEST
 
 TEST(GtestCheckDeathTest, DiesWithCorrectOutputOnFailure) {
   const bool a_false_condition = false;