Add implementation for hwbinder benchmark service.

Bug:32279499
Test: make android.hardware.tests.libhwbinder@1.0-impl
Change-Id: I75056afa32b8189020608779ec495659ea35ed48
diff --git a/tests/libhwbinder/1.0/default/Benchmark.cpp b/tests/libhwbinder/1.0/default/Benchmark.cpp
new file mode 100644
index 0000000..47b0ea0
--- /dev/null
+++ b/tests/libhwbinder/1.0/default/Benchmark.cpp
@@ -0,0 +1,28 @@
+#define LOG_TAG "libhwbinder_benchmark"
+
+#include "Benchmark.h"
+
+namespace android {
+namespace hardware {
+namespace tests {
+namespace libhwbinder {
+namespace V1_0 {
+namespace implementation {
+
+Return<void> Benchmark::sendVec(
+        const ::android::hardware::hidl_vec<uint8_t>& data,
+        sendVec_cb _hidl_cb) {
+    _hidl_cb(data);
+    return Void();
+}
+
+IBenchmark* HIDL_FETCH_IBenchmark(const char* /* name */) {
+    return new Benchmark();
+}
+
+}  // namespace implementation
+}  // namespace V1_0
+}  // namespace libhwbinder
+}  // namespace tests
+}  // namespace hardware
+}  // namespace android