cc: Add UMA for tracking decode duration for out of raster decodes.

cc/tiles/image_controller.cc

Index: cc/tiles/image_controller.cc
diff --git a/cc/tiles/image_controller.cc b/cc/tiles/image_controller.cc
index e8021e4264e0f41845b646f9fa974b3c3c4910d2..a46211dfa6325e7ce7ede8bd6680bbf464398244 100644
--- a/cc/tiles/image_controller.cc
+++ b/cc/tiles/image_controller.cc
@@ -179,7 +179,8 @@ std::vector<scoped_refptr<TileTask>> ImageController::SetPredecodeImages(
 
 ImageController::ImageDecodeRequestId ImageController::QueueImageDecode(
     sk_sp<const SkImage> image,
-    const ImageDecodedCallback& callback) {
+    const ImageDecodedCallback& callback,
+    ImageDecodeCache::ImageDecodeType type) {
   // We must not receive any image requests if we have no worker.
   CHECK(worker_task_runner_);
 
@@ -207,15 +208,15 @@ ImageController::ImageDecodeRequestId ImageController::QueueImageDecode(
   bool need_unref = false;
   if (is_image_lazy) {
     need_unref =
-        cache_->GetOutOfRasterDecodeTaskForImageAndRef(draw_image, &task);
+        cache_->GetOutOfRasterDecodeTaskForImageAndRef(draw_image, type, &task);
   }
   // If we don't need to unref this, we don't actually have a task.
   DCHECK(need_unref || !task);
 
   // Schedule the task and signal that there is more work.
   base::AutoLock hold(lock_);
-  image_decode_queue_[id] =
-      ImageDecodeRequest(id, draw_image, callback, std::move(task), need_unref);
+  image_decode_queue_[id] = ImageDecodeRequest(
+      id, draw_image, callback, std::move(task), need_unref, type);
 
   // If this is the only image decode request, schedule a task to run.
   // Otherwise, the task will be scheduled in the previou task's completion.
@@ -346,7 +347,7 @@ void ImageController::GenerateTasksForOrphanedRequests() {
     if (request.draw_image.image()->isLazyGenerated()) {
       // Get the task for this decode.
       request.need_unref = cache_->GetOutOfRasterDecodeTaskForImageAndRef(
-          request.draw_image, &request.task);
+          request.draw_image, request.decode_type, &request.task);
     }
     image_decode_queue_[request.id] = std::move(request);
   }
@@ -367,12 +368,14 @@ ImageController::ImageDecodeRequest::ImageDecodeRequest(
     const DrawImage& draw_image,
     const ImageDecodedCallback& callback,
     scoped_refptr<TileTask> task,
-    bool need_unref)
+    bool need_unref,
+    ImageDecodeCache::ImageDecodeType decode_type)
     : id(id),
       draw_image(draw_image),
       callback(callback),
       task(std::move(task)),
-      need_unref(need_unref) {}
+      need_unref(need_unref),
+      decode_type(decode_type) {}
 ImageController::ImageDecodeRequest::ImageDecodeRequest(
     ImageDecodeRequest&& other) = default;
 ImageController::ImageDecodeRequest::ImageDecodeRequest(