Change DownloadProcessHandle to be more of an encapsulated class.

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 f2cc38416a9b55982d4bd73c5a592da86ec1103e..8b5dc01900f5ffeec2783bd2fe0a1e13de31219d 100644
--- a/chrome/browser/download/download_item.cc
+++ b/chrome/browser/download/download_item.cc
@@ -152,7 +152,7 @@ DownloadItem::DownloadItem(DownloadManager* download_manager,
                   info.has_user_gesture, info.prompt_user_for_save_location,
                   info.path_uniquifier, false, false,
                   info.is_extension_install),
-      process_handle_(info.process_handle),
+      request_handle_(info.request_handle),
       download_id_(info.download_id),
       full_path_(info.path),
       url_chain_(info.url_chain),
@@ -458,7 +458,10 @@ void DownloadItem::Rename(const FilePath& full_path) {
 
 void DownloadItem::TogglePause() {
   DCHECK(IsInProgress());
-  download_manager_->PauseDownload(download_id_, !is_paused_);
+  if (is_paused_)
+    request_handle_.ResumeRequest();
+  else
+    request_handle_.PauseRequest();
   is_paused_ = !is_paused_;
   UpdateObservers();
 }