Change DownloadProcessHandle to be more of an encapsulated class.

chrome/browser/download/download_process_handle.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/download/download_process_handle.h"
-
-#include "chrome/browser/profiles/profile.h"
-#include "chrome/browser/tab_contents/tab_util.h"
-#include "content/browser/browser_thread.h"
-#include "content/browser/tab_contents/tab_contents.h"
-
-DownloadProcessHandle::DownloadProcessHandle()
-    : child_id_(-1), render_view_id_(-1), request_id_(-1) {
-}
-
-DownloadProcessHandle::DownloadProcessHandle(int child_id,
-                                             int render_view_id,
-                                             int request_id)
-    : child_id_(child_id),
-      render_view_id_(render_view_id),
-      request_id_(request_id) {
-}
-
-TabContents* DownloadProcessHandle::GetTabContents() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return tab_util::GetTabContentsByID(child_id_, render_view_id_);
-}
-
-DownloadManager* DownloadProcessHandle::GetDownloadManager() {
-  TabContents* contents = GetTabContents();
-  if (!contents)
-    return NULL;
-
-  Profile* profile = contents->profile();
-  if (!profile)
-    return NULL;
-
-  return profile->GetDownloadManager();
-}