Fix flaky linux panel tests related to active state checks

chrome/browser/ui/panels/detached_panel_browsertest.cc

 // Copyright (c) 2012 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 "base/message_loop.h"
 #include "chrome/browser/ui/panels/base_panel_browser_test.h"
 #include "chrome/browser/ui/panels/detached_panel_strip.h"
 #include "chrome/browser/ui/panels/native_panel.h"
 #include "chrome/browser/ui/panels/panel.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
@@ skipping 117 matching lines @@
   EXPECT_FALSE(panel->IsMinimized());
 
   test_panel->PressLeftMouseButtonTitlebar(panel->GetBounds().origin(),
                                            panel::APPLY_TO_ALL);
   test_panel->ReleaseMouseButtonTitlebar(panel::APPLY_TO_ALL);
   EXPECT_TRUE(panel->IsActive());
   EXPECT_FALSE(panel->IsMinimized());
 
   // Create a second panel to cause the first to become inactive.
   CreateDetachedPanel("2", gfx::Rect(100, 200, 230, 345));
-  EXPECT_FALSE(panel->IsActive());
+  WaitForPanelActiveState(panel, SHOW_AS_INACTIVE);
 
   // Clicking on an inactive detached panel's titlebar activates it.
   test_panel->PressLeftMouseButtonTitlebar(panel->GetBounds().origin());
   test_panel->ReleaseMouseButtonTitlebar();
   WaitForPanelActiveState(panel, SHOW_AS_ACTIVE);
   EXPECT_FALSE(panel->IsMinimized());
 
   panel_manager->CloseAll();
 }
 
 #endif // OS_MACOSX