Initialize DBus in mojo:ash on chrome os

ash/mus/bridge/wm_shell_mus.cc

Index: ash/mus/bridge/wm_shell_mus.cc
diff --git a/ash/mus/bridge/wm_shell_mus.cc b/ash/mus/bridge/wm_shell_mus.cc
index 6c42ca318b2511a8f6fbb49a1166f872ad9a3647..582e75000da983f3d73a1f2246e655e823cc131f 100644
--- a/ash/mus/bridge/wm_shell_mus.cc
+++ b/ash/mus/bridge/wm_shell_mus.cc
@@ -99,6 +99,8 @@ WmShellMus::WmShellMus(ShellDelegate* delegate, ::ui::WindowTreeClient* client)
   client_->AddObserver(this);
   WmShell::Set(this);
 
+  CreateMaximizeModeController();
+
   CreateMruWindowTracker();
 
   accessibility_delegate_.reset(new DefaultAccessibilityDelegate);
@@ -108,6 +110,9 @@ WmShellMus::WmShellMus(ShellDelegate* delegate, ::ui::WindowTreeClient* client)
 WmShellMus::~WmShellMus() {
   // This order mirrors that of Shell.
 
+  // Destroy maximize mode controller early on since it has some observers which
+  // need to be removed.
+  DeleteMaximizeModeController();
   DeleteSystemTrayDelegate();
   DeleteWindowSelectorController();
   DeleteMruWindowTracker();