Coverity: Pass parameters by reference.

chrome/browser/accessibility/browser_accessibility_win.cc

 // 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.
 
 #include "chrome/browser/accessibility/browser_accessibility_win.h"
 
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/accessibility/browser_accessibility_manager_win.h"
@@ skipping 1175 matching lines @@
 
   if (str.empty())
     return S_FALSE;
 
   *value_bstr = SysAllocString(str.c_str());
   DCHECK(*value_bstr);
 
   return S_OK;
 }
 
-string16 BrowserAccessibilityWin::Escape(string16 str) {
+string16 BrowserAccessibilityWin::Escape(const string16& str) {
   return EscapeQueryParamValueUTF8(str, false);
 }
 
 const string16& BrowserAccessibilityWin::TextForIAccessibleText() {
   if (role_ == WebAccessibility::ROLE_TEXT_FIELD) {
     return value_;
   } else {
     return name_;
   }
 }
@@ skipping 378 matching lines @@
   }
 
   // The role should always be set.
   DCHECK(!role_name_.empty() || ia_role_);
 
   // If we didn't explicitly set the IAccessible2 role, make it the same
   // as the MSAA role.
   if (!ia2_role_)
     ia2_role_ = ia_role_;
 }