Isolate initiation counts for downloads to their own histograms and improve

content/browser/tab_contents/tab_contents.cc

Index: content/browser/tab_contents/tab_contents.cc
diff --git a/content/browser/tab_contents/tab_contents.cc b/content/browser/tab_contents/tab_contents.cc
index 1fc4bfafe34850528a930836d3c77b2f160f64f0..37fb5308ab7cfa8238bed7112b0db1283ea83be9 100644
--- a/content/browser/tab_contents/tab_contents.cc
+++ b/content/browser/tab_contents/tab_contents.cc
@@ -945,8 +945,8 @@ void TabContents::OnSavePage() {
                        true,  // prefer_cache
                        save_info,
                        this);
-      download_stats::RecordDownloadCount(
-          download_stats::INITIATED_BY_SAVE_PACKAGE_FAILURE_COUNT);
+      download_stats::RecordDownloadSource(
+          download_stats::INITIATED_BY_SAVE_PACKAGE_FAILURE);
       return;
     }
   }
@@ -1425,6 +1425,8 @@ void TabContents::OnUpdateZoomLimits(int minimum_percent,
 }
 
 void TabContents::OnSaveURL(const GURL& url) {
+  download_stats::RecordDownloadSource(
+      download_stats::INITIATED_BY_RENDERER_SAVE);

[cbentzel, 2012/02/06 19:57:29]

Perhaps INITIATED_BY_PEPPER_SAVE? I guess we don't differentiate here. 

[Randy Smith (Not in Mondays), 2012/02/07 18:20:18]

Yeah; from the browser process perspective the distinction is
ViewHostMsg_{DownloadUrl, SaveURLAs}.  I'm open to different names for the enum
values if you have them, but I don't feel certain enough in my own heart that
the only place we could ever get that IPC is from pepper to call it out to
pepper.  But if you do, I'll change it.

[cbentzel, 2012/02/07 18:29:32]

Right now it's only from Pepper. If you merge/rebase you'll see that I've
commented this function to indicate that as well.

[Randy Smith (Not in Mondays), 2012/02/07 19:28:14]

Done.

   DownloadManager* dlm = GetBrowserContext()->GetDownloadManager();
   DownloadSaveInfo save_info;
   save_info.prompt_for_save_location = true;