wm: Update namespace and header define guards.

src/platform/window_manager/panel_bar.h

Index: src/platform/window_manager/panel_bar.h
diff --git a/src/platform/window_manager/panel_bar.h b/src/platform/window_manager/panel_bar.h
index 9977d924f35fa6354b3aca7aab8a4937645f4fc4..adc70c4ffdf5a40598a2c20845ed397eb5e111d3 100644
--- a/src/platform/window_manager/panel_bar.h
+++ b/src/platform/window_manager/panel_bar.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef __PLATFORM_WINDOW_MANAGER_PANEL_BAR_H__
-#define __PLATFORM_WINDOW_MANAGER_PANEL_BAR_H__
+#ifndef WINDOW_MANAGER_PANEL_BAR_H_
+#define WINDOW_MANAGER_PANEL_BAR_H_
 
 extern "C" {
 #include <X11/Xlib.h>
@@ -23,7 +23,7 @@ extern "C" {
 
 typedef ::Window XWindow;
 
-namespace chromeos {
+namespace window_manager {
 
 class Panel;
 class Shadow;
@@ -253,6 +253,6 @@ class PanelBar : public EventConsumer {
   DISALLOW_COPY_AND_ASSIGN(PanelBar);
 };
 
-}  // namespace chromeos
+}  // namespace window_manager
 
 #endif