Improve panel tests by properly waiting for expected conditions.

chrome/browser/ui/panels/test_panel_strip_squeeze_observer.h

+// 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.
+
+#ifndef CHROME_BROWSER_UI_PANELS_TEST_PANEL_STRIP_SQUEEZE_OBSERVER_H_
+#define CHROME_BROWSER_UI_PANELS_TEST_PANEL_STRIP_SQUEEZE_OBSERVER_H_
+
+#include "chrome/browser/ui/panels/test_panel_notification_observer.h"
+
+class DockedPanelStrip;
+class Panel;
+
+// Custom notification observer for waiting on panel strip that squeezes
+// its panels to reflect a certain state.
+// Modeled after ui_test_utils notification observers.
+class PanelStripSqueezeObserver : public TestPanelNotificationObserver {
+ public:
+  // Register to listen for panel strip updated notifications
+  // from the specified strip to detect a change to the state
+  // where the |active_panel| is at full width and all other
+  // panels in the strip are squeezed.
+  PanelStripSqueezeObserver(DockedPanelStrip* strip, Panel* active_panel);
+  virtual ~PanelStripSqueezeObserver();
+
+ private:
+  // TestNotificationObserver override:
+  virtual bool AtExpectedState() OVERRIDE;
+
+  bool IsSqueezed(Panel* panel);
+
+  DockedPanelStrip* panel_strip_;
+  Panel* active_panel_;
+
+  DISALLOW_COPY_AND_ASSIGN(PanelStripSqueezeObserver);
+};
+
+#endif  // CHROME_BROWSER_UI_PANELS_TEST_PANEL_STRIP_SQUEEZE_OBSERVER_H_