Log start of the test to logcat

This makes it easier to associate logs written during the test with the
test case that was running.

Test: atest CtsInitTestCases
Change-Id: I832f1c9ba8358341c934fdd91a65f5739bc98e37
diff --git a/init/init_test.cpp b/init/init_test.cpp
index fa65740..8550ec8 100644
--- a/init/init_test.cpp
+++ b/init/init_test.cpp
@@ -17,6 +17,7 @@
 #include <functional>
 
 #include <android-base/file.h>
+#include <android-base/logging.h>
 #include <android-base/properties.h>
 #include <gtest/gtest.h>
 
@@ -268,6 +269,17 @@
     ASSERT_EQ(1u, parser.parse_error_count());
 }
 
+class TestCaseLogger : public ::testing::EmptyTestEventListener {
+    void OnTestStart(const ::testing::TestInfo& test_info) override {
+#ifdef __ANDROID__
+        LOG(INFO) << "===== " << test_info.test_suite_name() << "::" << test_info.name() << " ("
+                  << test_info.file() << ":" << test_info.line() << ")";
+#else
+        UNUSED(test_info);
+#endif
+    }
+};
+
 }  // namespace init
 }  // namespace android
 
@@ -284,5 +296,6 @@
     }
 
     testing::InitGoogleTest(&argc, argv);
+    testing::UnitTest::GetInstance()->listeners().Append(new android::init::TestCaseLogger());
     return RUN_ALL_TESTS();
 }