[Sync] Componentize synced_tab_delegate

chrome/browser/sync/glue/synced_tab_delegate_desktop.cc

-// Copyright 2015 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/sync/glue/synced_tab_delegate.h"
-#include "chrome/browser/ui/sync/browser_synced_window_delegates_getter.h"
-#include "chrome/browser/ui/sync/tab_contents_synced_tab_delegate.h"
-
-// This should be the version of ImplFromWebContents that's pulled in for non-
-// android/ios builds. This is the standard content::WebContentsUserData way.
-// SyncedTabDelegateAndroid is a little bit funky, and does this differently.
-// Since SyncedTabDelegateAndroid implements most of its functionality by
-// invoking TabContentsSyncedTabDelegate, this is the only SyncedTabDelegate
-// piece that avoids being included in android builds.
-
-namespace browser_sync {
-
-// static
-SyncedTabDelegate* SyncedTabDelegate::ImplFromWebContents(
-    content::WebContents* web_contents) {
-  SyncedTabDelegate* delegate =
-      TabContentsSyncedTabDelegate::FromWebContents(web_contents);
-  if (!delegate) {
-    return nullptr;
-  }
-  delegate->SetSyncedWindowGetter(make_scoped_ptr(
-      new BrowserSyncedWindowDelegatesGetter()));
-  return delegate;
-}
-
-} // namespace browser_sync