Attempting to reland the Overview Button Change.

ash/wm/maximize_mode/maximize_mode_window_manager.cc

Index: ash/wm/maximize_mode/maximize_mode_window_manager.cc
diff --git a/ash/wm/maximize_mode/maximize_mode_window_manager.cc b/ash/wm/maximize_mode/maximize_mode_window_manager.cc
index 6858f36e0a9e9e68fe33ee9fd501c88fb639ecf0..24be9cbf19b843a3d673b521888b8ad3213e7c8a 100644
--- a/ash/wm/maximize_mode/maximize_mode_window_manager.cc
+++ b/ash/wm/maximize_mode/maximize_mode_window_manager.cc
@@ -22,6 +22,7 @@ MaximizeModeWindowManager::~MaximizeModeWindowManager() {
   EnableBackdropBehindTopWindowOnEachDisplay(false);
   RemoveWindowCreationObservers();
   RestoreAllWindows();
+  Shell::GetInstance()->OnMaximizeModeEnded();
 }
 
 int MaximizeModeWindowManager::GetNumberOfManagedWindows() {
@@ -93,6 +94,7 @@ MaximizeModeWindowManager::MaximizeModeWindowManager()
   MaximizeAllWindows();
   AddWindowCreationObservers();
   EnableBackdropBehindTopWindowOnEachDisplay(true);
+  Shell::GetInstance()->OnMaximizeModeStarted();
   Shell::GetScreen()->AddObserver(this);
   Shell::GetInstance()->AddShellObserver(this);
 }