Add a component updater for the CLD2 data file.

chrome/browser/component_updater/url_fetcher_downloader.cc

Index: chrome/browser/component_updater/url_fetcher_downloader.cc
diff --git a/chrome/browser/component_updater/url_fetcher_downloader.cc b/chrome/browser/component_updater/url_fetcher_downloader.cc
index 4d2f0e2b490f63d3345a01046f05505979b2bb79..c4b71101496a7cba007c7e44c9b669b16a616ccc 100644
--- a/chrome/browser/component_updater/url_fetcher_downloader.cc
+++ b/chrome/browser/component_updater/url_fetcher_downloader.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/component_updater/url_fetcher_downloader.h"
 
+#include "base/logging.h"
 #include "chrome/browser/component_updater/component_updater_utils.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/base/load_flags.h"
@@ -43,6 +44,7 @@ void UrlFetcherDownloader::DoStartDownload(const GURL& url) {
   url_fetcher_->SetAutomaticallyRetryOn5xx(false);
   url_fetcher_->SaveResponseToTemporaryFile(task_runner_);
 
+  VLOG(1) << "Starting background download: " << url.spec();
   url_fetcher_->Start();
 
   download_start_time_ = base::Time::Now();
@@ -79,6 +81,12 @@ void UrlFetcherDownloader::OnURLFetchComplete(const net::URLFetcher* source) {
   download_metrics.bytes_total = total_bytes_;
   download_metrics.download_time_ms = download_time.InMilliseconds();
 
+  base::FilePath local_path_;
+  source->GetResponseAsFilePath(false, &local_path_);
+  VLOG(1) << "Downloaded " << downloaded_bytes_ << " bytes in "
+      << download_time.InMilliseconds() << "ms from "
+      << source->GetURL().spec()
+      << " to " << local_path_.value();
   CrxDownloader::OnDownloadComplete(is_handled, result, download_metrics);
 }