Fix minor issues in ChromeDriver.

chrome/test/webdriver/webdriver_error.cc

 // 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/test/webdriver/webdriver_error.h"
 
 #include <sstream>
 
 namespace webdriver {
 
@@ skipping 54 matching lines @@
 
 std::string Error::ToString() const {
   std::string error;
   if (code_ != kUnknownError) {
     error += ErrorCodeToString(code_);
     error += ": ";
   }
   if (details_.length()) {
     error += details_;
   }
+
+  // Only include a stacktrace on Linux. Windows and Mac have all symbols
+  // stripped in release builds.
+#if defined(OS_LINUX)
   size_t count = 0;
   trace_.Addresses(&count);
   if (count > 0) {
     std::ostringstream ostream;
     trace_.OutputToStream(&ostream);
     error += "\n";
     error += ostream.str();
   }
+#endif
   return error;
 }
 
 ErrorCode Error::code() const {
   return code_;
 }
 
 const std::string& Error::details() const {
   return details_;
 }
 
 const base::debug::StackTrace& Error::trace() const {
   return trace_;
 }
 
 }  // namespace webdriver