Coverity PASS_BY_VALUE fix.

chrome/browser/ui/gtk/extensions/shell_window_gtk.cc

 // 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/gtk/extensions/shell_window_gtk.h"
 
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/extensions/extension.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
 #include "ui/base/x/active_window_watcher_x.h"
 #include "ui/gfx/rect.h"
 
 ShellWindowGtk::ShellWindowGtk(Profile* profile,
                                const extensions::Extension* extension,
                                const GURL& url,
-                               const ShellWindow::CreateParams params)
+                               const ShellWindow::CreateParams& params)
     : ShellWindow(profile, extension, url),
       state_(GDK_WINDOW_STATE_WITHDRAWN),
       is_active_(!ui::ActiveWindowWatcherX::WMSupportsActivation()) {
   window_ = GTK_WINDOW(gtk_window_new(GTK_WINDOW_TOPLEVEL));
 
   gfx::NativeView native_view =
       web_contents()->GetView()->GetNativeView();
   gtk_container_add(GTK_CONTAINER(window_), native_view);
 
   gtk_window_set_default_size(
@@ skipping 138 matching lines @@
 gboolean ShellWindowGtk::OnWindowState(GtkWidget* sender,
                                        GdkEventWindowState* event) {
   state_ = event->new_window_state;
   return FALSE;
 }
 
 // static
 ShellWindow* ShellWindow::CreateImpl(Profile* profile,
                                      const extensions::Extension* extension,
                                      const GURL& url,
-                                     const ShellWindow::CreateParams params) {
+                                     const ShellWindow::CreateParams& params) {
   return new ShellWindowGtk(profile, extension, url, params);
 }