Put history insertion for downloads processing inline.

chrome/browser/download/download_item.cc

Index: chrome/browser/download/download_item.cc
diff --git a/chrome/browser/download/download_item.cc b/chrome/browser/download/download_item.cc
index f87045109c37ee804255d3b9a655d902ef12a2ab..0139a0d1530eb46613e2d6a5bd74e9e8fc7d3922 100644
--- a/chrome/browser/download/download_item.cc
+++ b/chrome/browser/download/download_item.cc
@@ -27,6 +27,23 @@
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/pref_names.h"
 
+// A DownloadItem normally goes through the following states:
+//      * Created (when download starts)
+//      * Made visible to consumers (e.g. Javascript) after the
+//        destination file has been determined.
+//      * Entered into the history database.
+//      * Made visible in the download shelf.
+//      * All data is received.  Note that the actual data download occurs
+//        in parallel with the above steps, but until those steps are
+//        complete, completion of the data download will be ignored.
+//      * Download file is renamed to its final name, and possibly
+//        auto-opened.
+// TODO(rdsmith): This progress should be reflected in
+// DownloadItem::DownloadState and a state transition table/state diagram.
+//
+// TODO(rdsmith): This description should be updated to reflect the cancel
+// pathways.
+
 namespace {
 
 // Update frequency (milliseconds).