Implement Instant on Mac

chrome/browser/cocoa/browser_window_controller_private.mm

 // Copyright (c) 2010 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.
 
 #import "chrome/browser/cocoa/browser_window_controller_private.h"
 
 #include "base/mac_util.h"
 #import "base/scoped_nsobject.h"
 #include "chrome/browser/browser.h"
 #include "chrome/browser/browser_list.h"
@@ skipping 432 matching lines @@
 
 - (BOOL)shouldShowBookmarkBar {
   DCHECK(browser_.get());
   return browser_->profile()->GetPrefs()->GetBoolean(prefs::kShowBookmarkBar) ?
       YES : NO;
 }
 
 - (BOOL)shouldShowDetachedBookmarkBar {
   DCHECK(browser_.get());
   TabContents* contents = browser_->GetSelectedTabContents();
-  return (contents && contents->ShouldShowBookmarkBar()) ? YES : NO;
+  return (contents &&
+          contents->ShouldShowBookmarkBar() &&
+          ![previewableContentsController_ isShowingPreview]);
 }
 
 - (void)adjustToolbarAndBookmarkBarForCompression:(CGFloat)compression {
   CGFloat newHeight =
       [toolbarController_ desiredHeightForCompression:compression];
   NSRect toolbarFrame = [[toolbarController_ view] frame];
   CGFloat deltaH = newHeight - toolbarFrame.size.height;
 
   if (deltaH == 0)
     return;
@@ skipping 34 matching lines @@
 - (void)disableBarVisibilityUpdates {
   // Early escape if there's nothing to do.
   if (!barVisibilityUpdatesEnabled_)
     return;
 
   barVisibilityUpdatesEnabled_ = NO;
   [fullscreenController_ cancelAnimationAndTimers];
 }
 
 @end  // @implementation BrowserWindowController(Private)