cc: Add image decode queue functionality to image manager.

cc/BUILD.gn

Index: cc/BUILD.gn
diff --git a/cc/BUILD.gn b/cc/BUILD.gn
index 7b8bb2b659bdaea21d92410eed34f212e34df7c2..d16ec63ba57d8b8cbf0173c754313734f8f878ff 100644
--- a/cc/BUILD.gn
+++ b/cc/BUILD.gn
@@ -422,6 +422,8 @@ cc_component("cc") {
     "scheduler/scheduler_state_machine.cc",
     "scheduler/scheduler_state_machine.h",
     "scheduler/video_frame_controller.h",
+    "tiles/decoded_image_tracker.cc",
+    "tiles/decoded_image_tracker.h",
     "tiles/eviction_tile_priority_queue.cc",
     "tiles/eviction_tile_priority_queue.h",
     "tiles/gpu_image_decode_cache.cc",
@@ -885,6 +887,7 @@ cc_test("cc_unittests") {
     "test/mock_helper_unittest.cc",
     "test/ordered_simple_task_runner_unittest.cc",
     "test/test_web_graphics_context_3d_unittest.cc",
+    "tiles/decoded_image_tracker_unittest.cc",
     "tiles/gpu_image_decode_cache_unittest.cc",
     "tiles/image_controller_unittest.cc",
     "tiles/mipmap_util_unittest.cc",