Update Panel mininimize/restore button on strip and expansion state change.

chrome/browser/ui/panels/panel_browser_window_cocoa.mm

 // 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 "chrome/browser/ui/panels/panel_browser_window_cocoa.h"
 
 #include "base/auto_reset.h"
 #include "base/logging.h"
 #include "chrome/browser/tabs/tab_strip_model.h"
 #include "chrome/browser/ui/browser.h"
@@ skipping 266 matching lines @@
 }
 
 void PanelBrowserWindowCocoa::DestroyPanelBrowser() {
   [controller_ close];
 }
 
 void PanelBrowserWindowCocoa::EnsurePanelFullyVisible() {
   [controller_ ensureFullyVisible];
 }
 
-void PanelBrowserWindowCocoa::SetPanelAppIconVisibility(bool visible) {
-  // TODO(dimich): to be implemented.
-}
-
 void PanelBrowserWindowCocoa::SetPanelAlwaysOnTop(bool on_top) {
   [controller_ updateWindowLevel];
 }
 
 void PanelBrowserWindowCocoa::EnableResizeByMouse(bool enable) {
   [controller_ enableResizeByMouse:enable];
 }
 
+void PanelBrowserWindowCocoa::UpdateMinimizeRestoreButtonVisibility() {
+  [controller_ updateTitleBarMinimizeRestoreButtonVisibility];
+}
+
 void PanelBrowserWindowCocoa::DidCloseNativeWindow() {
   DCHECK(!isClosed());
   panel_->OnNativePanelClosed();
   controller_ = NULL;
 }
 
 gfx::Size PanelBrowserWindowCocoa::WindowSizeFromContentSize(
     const gfx::Size& content_size) const {
   NSWindow* window = [controller_ window];
   NSRect content = NSMakeRect(0, 0,
@@ skipping 130 matching lines @@
       return ![[titlebar() closeButton] isHidden];
     case MINIMIZE_BUTTON:
       return ![[titlebar() minimizeButton] isHidden];
     case RESTORE_BUTTON:
       return ![[titlebar() restoreButton] isHidden];
     default:
       NOTREACHED();
   }
   return false;
 }