Clean up libcutils/libutils tests.

Move tests in the same directory as the corresponding code, so it's
easier to see what is/isn't tested.

Fix naming of libcutils_tests (plural) to match the singular that's more
common (even though the plural makes more sense to me).

Add these two to system/core/'s TEST_MAPPING.

Remove obsolete AndroidTest.xml.

Fix a flaky (timing-dependent) libcutils test.

Test: ran tests
Change-Id: I7e0a31ff45c8a152562bf66fc97161594249366e
diff --git a/libutils/Singleton_test.cpp b/libutils/Singleton_test.cpp
new file mode 100644
index 0000000..61084b0
--- /dev/null
+++ b/libutils/Singleton_test.cpp
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "Singleton_test"
+
+#include <dlfcn.h>
+
+#include <android-base/file.h>
+#include <android-base/stringprintf.h>
+#include <utils/Singleton.h>
+
+#include <gtest/gtest.h>
+
+#include "Singleton_test.h"
+
+namespace android {
+
+TEST(SingletonTest, bug35674422) {
+    std::string path = android::base::GetExecutableDirectory();
+    // libutils_test_singleton1.so contains the ANDROID_SINGLETON_STATIC_INSTANCE
+    // definition of SingletonTestData, load it first.
+    std::string lib = android::base::StringPrintf("%s/libutils_test_singleton1.so", path.c_str());
+    void* handle1 = dlopen(lib.c_str(), RTLD_NOW);
+    ASSERT_TRUE(handle1 != nullptr) << dlerror();
+
+    // libutils_test_singleton2.so references SingletonTestData but should not
+    // have a definition
+    lib = android::base::StringPrintf("%s/libutils_test_singleton2.so", path.c_str());
+    void* handle2 = dlopen(lib.c_str(), RTLD_NOW);
+    ASSERT_TRUE(handle2 != nullptr) << dlerror();
+
+    using has_fn_t = decltype(&singletonHasInstance);
+    using get_fn_t = decltype(&singletonGetInstanceContents);
+    using set_fn_t = decltype(&singletonSetInstanceContents);
+
+    has_fn_t has1 = reinterpret_cast<has_fn_t>(dlsym(handle1, "singletonHasInstance"));
+    ASSERT_TRUE(has1 != nullptr) << dlerror();
+    has_fn_t has2 = reinterpret_cast<has_fn_t>(dlsym(handle2, "singletonHasInstance"));
+    ASSERT_TRUE(has2 != nullptr) << dlerror();
+    get_fn_t get1 = reinterpret_cast<get_fn_t>(dlsym(handle1, "singletonGetInstanceContents"));
+    ASSERT_TRUE(get1 != nullptr) << dlerror();
+    get_fn_t get2 = reinterpret_cast<get_fn_t>(dlsym(handle2, "singletonGetInstanceContents"));
+    ASSERT_TRUE(get2 != nullptr) << dlerror();
+    set_fn_t set1 = reinterpret_cast<set_fn_t>(dlsym(handle2, "singletonSetInstanceContents"));
+    ASSERT_TRUE(set1 != nullptr) << dlerror();
+
+    EXPECT_FALSE(has1());
+    EXPECT_FALSE(has2());
+    set1(12345678U);
+    EXPECT_TRUE(has1());
+    EXPECT_TRUE(has2());
+    EXPECT_EQ(12345678U, get1());
+    EXPECT_EQ(12345678U, get2());
+}
+
+}