fix crash when identity.getAuthToken is called without an options parameter

chrome/browser/extensions/api/identity/identity_api.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/extensions/api/identity/identity_api.h"
 
 #include <set>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 307 matching lines @@
   if (oauth2_info.scopes.size() == 0) {
     error_ = identity_constants::kInvalidScopes;
     return false;
   }
 
   std::set<std::string> scopes(oauth2_info.scopes.begin(),
                                oauth2_info.scopes.end());
 
   std::string account_key = GetPrimaryAccountId(GetProfile());
 
-  if (params->details->account.get()) {
+  if (params->details.get() && params->details->account.get()) {
     std::string detail_key =
         extensions::IdentityAPI::GetFactoryInstance()
             ->Get(GetProfile())
             ->FindAccountKeyByGaiaId(params->details->account->id);
 
     if (detail_key != account_key) {
       if (detail_key.empty() || !switches::IsExtensionsMultiAccount()) {
         // TODO(courage): should this be a different error?
         error_ = identity_constants::kUserNotSignedIn;
         return false;
@@ skipping 516 matching lines @@
 void IdentityLaunchWebAuthFlowFunction::OnAuthFlowURLChange(
     const GURL& redirect_url) {
   if (redirect_url.GetWithEmptyPath() == final_url_prefix_) {
     SetResult(new base::StringValue(redirect_url.spec()));
     SendResponse(true);
     Release();  // Balanced in RunAsync.
   }
 }
 
 }  // namespace extensions