components/arc/video_accelerator: Add unittest for util function.

This CL adds tests for duplicateFD() function.

BUG=b:136716638
TEST=components_unittests --gtest_filter=ArcVideoAcceleratorUtil.*

Change-Id: Iae61b51fe7f5af5ca021ac11ff5e0764dff37044
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1828675Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Commit-Queue: Chih-Yu Huang <akahuang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723656}

components/arc/BUILD.gn

@@ -375,6 +375,7 @@ source_set("unit_tests") {
     "session/arc_vm_client_adapter_util_unittest.cc",
     "session/file_system_status_unittest.cc",
     "timer/arc_timer_bridge_unittest.cc",
+    "video_accelerator/arc_video_accelerator_util_unittest.cc",
     "wake_lock/arc_wake_lock_bridge_unittest.cc",
   ]
 
@@ -397,6 +398,7 @@ source_set("unit_tests") {
     "//chromeos/network:test_support",
     "//chromeos/system:system",
     "//components/account_id",
+    "//components/arc/video_accelerator",
     "//components/keyed_service/content",
     "//components/prefs:test_support",
     "//components/session_manager/core:core",

components/arc/video_accelerator/arc_video_accelerator_util_unittest.cc

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/arc/video_accelerator/arc_video_accelerator_util.h"
+
+#include "base/files/scoped_file.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace arc {
+
+namespace {
+constexpr char kTestData[] = "TEST_DATA";
+constexpr size_t kNumFds = 3;
+}  // namespace
+
+TEST(ArcVideoAcceleratorUtil, DuplicateFD_OK) {
+  base::ScopedFD fd = CreateTempFileForTesting(kTestData);
+  auto fds = DuplicateFD(std::move(fd), kNumFds);
+
+  EXPECT_EQ(fds.size(), kNumFds);
+}
+
+TEST(ArcVideoAcceleratorUtil, DuplicateFD_Fail) {
+  auto fds = DuplicateFD(base::ScopedFD(), kNumFds);
+
+  EXPECT_EQ(fds.size(), 0u);
+}
+
+}  // namespace arc