[ChromeDriver] Select the main frame if a non-existant child frame is targeted.

chrome/test/chromedriver/status.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/test/chromedriver/status.h"
 
 namespace {
 
 // Returns the string equivalent of the given |ErrorCode|.
 const char* DefaultMessageForStatusCode(StatusCode code) {
@@ skipping 13 matching lines @@
     case kUnknownError:
       return "unknown error";
     case kXPathLookupError:
       return "xpath lookup error";
     case kInvalidSelector:
       return "invalid selector";
     case kSessionNotCreatedException:
       return "session not created exception";
     case kNoSuchSession:
       return "no such session";
+    case kNoSuchFrame:
+      return "no such frame";
     case kChromeNotReachable:
       return "chrome not reachable";
     case kDisconnected:
       return "disconnected";
     default:
       return "<unknown>";
   }
 }
 
 }  // namespace
@@ skipping 29 matching lines @@
   return code_ != kOk;
 }
 
 StatusCode Status::code() const {
   return code_;
 }
 
 const std::string& Status::message() const {
   return msg_;
 }