Use Titlebar instead of TitleBar consistently in panels code.

chrome/browser/ui/panels/panel_browser_window_cocoa.mm

 // Copyright (c) 2011 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/logging.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/cocoa/find_bar/find_bar_bridge.h"
 #include "chrome/browser/ui/panels/panel.h"
@@ skipping 73 matching lines @@
   bounds_ = bounds;
   NSRect frame = ConvertCoordinatesToCocoa(bounds);
   [[controller_ window] setFrame:frame display:YES animate:YES];
 }
 
 void PanelBrowserWindowCocoa::OnPanelExpansionStateChanged(
     Panel::ExpansionState expansion_state) {
   NOTIMPLEMENTED();
 }
 
-bool PanelBrowserWindowCocoa::ShouldBringUpPanelTitleBar(int mouse_x,
+bool PanelBrowserWindowCocoa::ShouldBringUpPanelTitlebar(int mouse_x,
                                                          int mouse_y) const {
   NOTIMPLEMENTED();
   return false;
 }
 
 void PanelBrowserWindowCocoa::ClosePanel() {
   if (isClosed())
       return;
 
   NSWindow* window = [controller_ window];
@@ skipping 62 matching lines @@
   controller_ = NULL;
 }
 
 // NativePanelTesting implementation.
 
 // static
 NativePanelTesting* NativePanelTesting::Create(NativePanel* native_panel) {
   NOTIMPLEMENTED();
   return NULL;
 }