Fix use-after-move in //components/feed/core/v2/

Fix use-after-move (potential) bugs found by the
"bugprone-use-after-move" clang-tidy check.

Bug: 1122844
Change-Id: I7308e0fe69cf248829d11125456b3f43d2b7ae01
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2382074Reviewed-by: Dan H <harringtond@chromium.org>
Commit-Queue: Maksim Ivanov <emaxx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#803154}

components/feed/core/v2/image_fetcher.cc

@@ -47,7 +47,8 @@ void ImageFetcher::Fetch(const GURL& url, ImageCallback callback) {
 
   auto simple_loader = network::SimpleURLLoader::Create(
       std::move(resource_request), traffic_annotation);
-  simple_loader->DownloadToString(
+  auto* const simple_loader_ptr = simple_loader.get();
+  simple_loader_ptr->DownloadToString(
       url_loader_factory_.get(),
       base::BindOnce(&ImageFetcher::OnFetchComplete, weak_factory_.GetWeakPtr(),
                      std::move(simple_loader), std::move(callback)),