Remove DownloadManager::GetDownloadItem in favor of GetDownload()

chrome/browser/download/download_file_picker_chromeos.cc

Index: chrome/browser/download/download_file_picker_chromeos.cc
diff --git a/chrome/browser/download/download_file_picker_chromeos.cc b/chrome/browser/download/download_file_picker_chromeos.cc
index fa4596cd314d04b4caa80949845d5a71ac5518de..dc3103e57be05b6554f02bbb1075980fbfa4cdf2 100644
--- a/chrome/browser/download/download_file_picker_chromeos.cc
+++ b/chrome/browser/download/download_file_picker_chromeos.cc
@@ -54,8 +54,7 @@ void DownloadFilePickerChromeOS::FileSelectedWithExtraInfo(
   RecordFileSelected(path);
 
   if (download_manager_) {
-    content::DownloadItem* download =
-        download_manager_->GetActiveDownloadItem(download_id_);

[Randy Smith (Not in Mondays), 2012/09/11 19:02:21]

Huh.  Does this path handle null downloads?  If so, same comment as in cdmd.cc. 
If not, I'm surprised we haven't crashed previously--we need better cancel
tests.

[benjhayden, 2012/09/12 18:17:25]

SubstituteDriveDownloadPath calls SetDownloadParams(), which returns early if
!download, but then SDDP also does some other stuff. I'd rather not make it not
do that other stuff in this CL.

[Randy Smith (Not in Mondays), 2012/09/13 18:52:43]

I understand about wanting to avoid mission creep, but if the code is resilient
to null downloads in some fashion, that may mean that you're changing behavior
by making cancelled downloads actually show up now.  I think you need to grok
the code well enough to figure out if that's ok (or test against IN_PROGRESS
here) for this CL.

[benjhayden, 2012/09/13 20:19:35]

Ah! Good idea.
I added the IN_PROGRESS test in DriveDownloadObserver::SetDownloadParams in
chrome/browser/chromeos/gdata/drive_download_observer.cc
I'll make sure to ask achuith about it unless tests turn up a specific reason to
not test for IN_PROGRESS.

+    DownloadItem* download = download_manager_->GetDownload(download_id_);
     gdata::DriveDownloadObserver::SubstituteDriveDownloadPath(
         NULL, path, download,
         base::Bind(&DownloadFilePickerChromeOS::OnFileSelected,