cc: Add image decode queue functionality to image manager.

cc/tiles/decoded_image_tracker_unittest.cc

+// Copyright 2016 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 <vector>
+
+#include "base/bind.h"
+#include "cc/tiles/decoded_image_tracker.h"
+#include "cc/tiles/image_controller.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace cc {
+
+class TestImageController : public ImageController {
+ public:
+  TestImageController() : ImageController(nullptr, nullptr) {}
+
+  void UnlockImageDecode(ImageDecodeRequestId id) override {
+    auto it = std::find(locked_ids_.begin(), locked_ids_.end(), id);
+    ASSERT_FALSE(it == locked_ids_.end());
+    locked_ids_.erase(it);
+  }
+
+  ImageDecodeRequestId QueueImageDecode(
+      sk_sp<const SkImage> image,
+      const ImageDecodedCallback& callback) override {
+    auto id = next_id_++;
+    locked_ids_.push_back(id);
+    callback.Run(id);
+    return id;
+  }
+
+  size_t num_locked_images() { return locked_ids_.size(); }
+
+ private:
+  ImageDecodeRequestId next_id_ = 1;
+  std::vector<ImageDecodeRequestId> locked_ids_;
+};
+
+class DecodedImageTrackerTest : public testing::Test {
+ public:
+  void SetUp() override {
+    decoded_image_tracker_.set_image_controller(image_controller());
+  }
+
+  TestImageController* image_controller() { return &image_controller_; }
+  DecodedImageTracker* decoded_image_tracker() {
+    return &decoded_image_tracker_;
+  }
+
+ private:
+  TestImageController image_controller_;
+  DecodedImageTracker decoded_image_tracker_;
+};
+
+TEST_F(DecodedImageTrackerTest, QueueImageLocksImages) {
+  bool locked = false;
+  decoded_image_tracker()->QueueImageDecode(
+      nullptr, base::Bind([](bool* locked) { *locked = true; },
+                          base::Unretained(&locked)));
+  EXPECT_TRUE(locked);
+  EXPECT_EQ(1u, image_controller()->num_locked_images());
+}
+
+TEST_F(DecodedImageTrackerTest, NotifyFrameFinishedUnlocksImages) {
+  bool locked = false;
+  decoded_image_tracker()->QueueImageDecode(
+      nullptr, base::Bind([](bool* locked) { *locked = true; },
+                          base::Unretained(&locked)));
+  EXPECT_TRUE(locked);
+  EXPECT_EQ(1u, image_controller()->num_locked_images());
+
+  decoded_image_tracker()->NotifyFrameFinished();
+  EXPECT_EQ(1u, image_controller()->num_locked_images());
+
+  locked = false;
+  decoded_image_tracker()->QueueImageDecode(
+      nullptr, base::Bind([](bool* locked) { *locked = true; },
+                          base::Unretained(&locked)));
+  EXPECT_TRUE(locked);
+  EXPECT_EQ(2u, image_controller()->num_locked_images());
+
+  decoded_image_tracker()->NotifyFrameFinished();
+  EXPECT_EQ(1u, image_controller()->num_locked_images());
+
+  decoded_image_tracker()->NotifyFrameFinished();
+  EXPECT_EQ(0u, image_controller()->num_locked_images());
+}
+
+}  // namespace cc