Fetch SDCH dictionary as soon as current URL fetch completes...

chrome/browser/net/sdch_dictionary_fetcher.h

Index: chrome/browser/net/sdch_dictionary_fetcher.h
===================================================================
--- chrome/browser/net/sdch_dictionary_fetcher.h	(revision 9302)
+++ chrome/browser/net/sdch_dictionary_fetcher.h	(working copy)
@@ -13,6 +13,7 @@
 #include <string>
 
 #include "base/compiler_specific.h"
+#include "base/scoped_ptr.h"
 #include "base/task.h"
 #include "chrome/browser/net/url_fetcher.h"
 #include "net/base/sdch_manager.h"
@@ -20,7 +21,7 @@
 class SdchDictionaryFetcher : public URLFetcher::Delegate,
                               public SdchFetcher {
  public:
-  SdchDictionaryFetcher() : 
+  SdchDictionaryFetcher() :
       ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)),
       task_is_pending_(false) {}
   virtual ~SdchDictionaryFetcher() {}
@@ -31,8 +32,11 @@
   virtual void Schedule(const GURL& dictionary_url);
 
  private:
-  // Delay between Schedule and actual download.
-  static const int kMsDelayFromRequestTillDownload = 15000;
+  // Delay in ms between Schedule and actual download.
+  // This leaves the URL in a queue, which is de-duped, so that there is less
+  // chance we'll try to load the same URL multiple times when a pile of
+  // page subresources (or tabs opened in parallel) all suggest the dictionary.
+  static const int kMsDelayFromRequestTillDownload = 100;
 
   // Ensure the download after the above delay.
   void ScheduleDelayedRun();