Teach sp<> how to std::move

Arguably we should migrate to std::shared_ptr
but for now make std::vector<sp<>> a bit less
horrible

Change-Id: Ia458a2daff0b656b2f3310b3ea100565ec844c69
diff --git a/libutils/tests/Android.mk b/libutils/tests/Android.mk
index 514f8c1..cb9e8a2 100644
--- a/libutils/tests/Android.mk
+++ b/libutils/tests/Android.mk
@@ -27,6 +27,7 @@
     Looper_test.cpp \
     LruCache_test.cpp \
     String8_test.cpp \
+    StrongPointer_test.cpp \
     Unicode_test.cpp \
     Vector_test.cpp \
 
diff --git a/libutils/tests/StrongPointer_test.cpp b/libutils/tests/StrongPointer_test.cpp
new file mode 100644
index 0000000..f46d6d1
--- /dev/null
+++ b/libutils/tests/StrongPointer_test.cpp
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
+#include <gtest/gtest.h>
+
+#include <utils/StrongPointer.h>
+#include <utils/RefBase.h>
+
+using namespace android;
+
+class Foo : public LightRefBase<Foo> {
+public:
+    Foo(bool* deleted_check) : mDeleted(deleted_check) {
+        *mDeleted = false;
+    }
+
+    ~Foo() {
+        *mDeleted = true;
+    }
+private:
+    bool* mDeleted;
+};
+
+TEST(StrongPointer, move) {
+    bool isDeleted;
+    Foo* foo = new Foo(&isDeleted);
+    ASSERT_EQ(0, foo->getStrongCount());
+    ASSERT_FALSE(isDeleted) << "Already deleted...?";
+    sp<Foo> sp1(foo);
+    ASSERT_EQ(1, foo->getStrongCount());
+    {
+        sp<Foo> sp2 = std::move(sp1);
+        ASSERT_EQ(1, foo->getStrongCount()) << "std::move failed, incremented refcnt";
+        ASSERT_EQ(nullptr, sp1.get()) << "std::move failed, sp1 is still valid";
+        // The strong count isn't increasing, let's double check the old object
+        // is properly reset and doesn't early delete
+        sp1 = std::move(sp2);
+    }
+    ASSERT_FALSE(isDeleted) << "deleted too early! still has a reference!";
+    {
+        // Now let's double check it deletes on time
+        sp<Foo> sp2 = std::move(sp1);
+    }
+    ASSERT_TRUE(isDeleted) << "foo was leaked!";
+}