Place primary screen before secondary screens in picker

chrome/browser/media/desktop_media_list_ash.cc

 // Copyright 2013 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/media/desktop_media_list_ash.h"
 
 #include <set>
 
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
@@ skipping 162 matching lines @@
     std::vector<DesktopMediaListAsh::SourceDescription>* sources) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
 
   aura::Window::Windows root_windows = ash::Shell::GetAllRootWindows();
 
   for (aura::Window::Windows::const_iterator iter = root_windows.begin();
        iter != root_windows.end(); ++iter) {
     if (source_types_ & SCREENS) {
       SourceDescription screen_source(
           content::DesktopMediaID::RegisterAuraWindow(*iter), (*iter)->title());
-      sources->push_back(screen_source);
+      if (*iter == ash::Shell::GetPrimaryRootWindow())
+        sources->insert(sources->begin(), screen_source);

[Sergey Ulanov, 2014/05/19 18:59:33]

nit: add {} here and for the else case.

+      else
+        sources->push_back(screen_source);
 
       CaptureThumbnail(screen_source.id, *iter);
     }
 
     if (source_types_ & WINDOWS) {
       EnumerateWindowsForRoot(
           sources, *iter, ash::kShellWindowId_DefaultContainer);
       EnumerateWindowsForRoot(
           sources, *iter, ash::kShellWindowId_AlwaysOnTopContainer);
       EnumerateWindowsForRoot(
@@ skipping 35 matching lines @@
   if (!pending_window_capture_requests_) {
     // Once we've finished capturing all windows post a task for the next list
     // update.
     BrowserThread::PostDelayedTask(
         BrowserThread::UI, FROM_HERE,
         base::Bind(&DesktopMediaListAsh::Refresh,
                    weak_factory_.GetWeakPtr()),
         update_period_);
   }
 }