graphics: add a default impl for IMapper 2.1

This is for reference only.  It almost only has stub implementations
for the new 2.1 methods.

Test: boots and VTS
Change-Id: I60499f3094df1975ccbbcda7b5c03d4a0dc57c39
diff --git a/graphics/mapper/2.1/default/passthrough.cpp b/graphics/mapper/2.1/default/passthrough.cpp
new file mode 100644
index 0000000..c7f0cf5
--- /dev/null
+++ b/graphics/mapper/2.1/default/passthrough.cpp
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2016 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 <android/hardware/graphics/mapper/2.1/IMapper.h>
+#include <mapper-passthrough/2.1/GrallocLoader.h>
+
+using android::hardware::graphics::mapper::V2_1::IMapper;
+using android::hardware::graphics::mapper::V2_1::passthrough::GrallocLoader;
+
+extern "C" IMapper* HIDL_FETCH_IMapper(const char* /*name*/) {
+    return GrallocLoader::load();
+}