Make DownloadHistory observe manager, items

chrome/browser/extensions/api/downloads/downloads_api.cc

Index: chrome/browser/extensions/api/downloads/downloads_api.cc
diff --git a/chrome/browser/extensions/api/downloads/downloads_api.cc b/chrome/browser/extensions/api/downloads/downloads_api.cc
index e4cc721dde93ab4c8fdf3ce47386cf429b176540..96f68379a00e113dfa6cdf1b0d2ff5472339e69c 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api.cc
+++ b/chrome/browser/extensions/api/downloads/downloads_api.cc
@@ -855,7 +855,7 @@ bool DownloadsGetFileIconFunction::RunImpl() {
   DownloadItem* download_item = manager->GetDownload(params->download_id);
   if (!download_item && incognito_manager)
     download_item = incognito_manager->GetDownload(params->download_id);
-  if (!download_item) {
+  if (!download_item || download_item->GetTargetFilePath().empty()) {
     // The DownloadItem is is added to history when the path is determined. If
     // the download is not in history, then we don't have a path / final
     // filename and no icon.
@@ -865,12 +865,11 @@ bool DownloadsGetFileIconFunction::RunImpl() {
   // In-progress downloads return the intermediate filename for GetFullPath()
   // which doesn't have the final extension. Therefore we won't be able to
   // derive a good file icon for it. So we use GetTargetFilePath() instead.
-  FilePath path = download_item->GetTargetFilePath();
-  DCHECK(!path.empty());
   DCHECK(icon_extractor_.get());
   DCHECK(icon_size == 16 || icon_size == 32);
   EXTENSION_FUNCTION_VALIDATE(icon_extractor_->ExtractIconURLForPath(
-      path, IconLoaderSizeFromPixelSize(icon_size),
+      download_item->GetTargetFilePath(),
+      IconLoaderSizeFromPixelSize(icon_size),
       base::Bind(&DownloadsGetFileIconFunction::OnIconURLExtracted, this)));
   return true;
 }