In case of an error in AutofillCounter's queries, do not crash.

components/browsing_data/core/counters/autofill_counter.cc

 // Copyright 2015 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 "components/browsing_data/core/counters/autofill_counter.h"
 
 #include <algorithm>
 #include <utility>
 #include <vector>
 
@@ skipping 63 matching lines @@
   credit_cards_query_ = web_data_service_->GetCreditCards(this);
 
   // Count the addresses.
   addresses_query_ = web_data_service_->GetAutofillProfiles(this);
 }
 
 void AutofillCounter::OnWebDataServiceRequestDone(
     WebDataServiceBase::Handle handle,
     std::unique_ptr<WDTypedResult> result) {
   DCHECK(thread_checker_.CalledOnValidThread());
+
   if (!result) {
+    // CancelAllRequests will cancel all queries that are active; the query that
+    // just failed is complete and cannot be canceled so zero it out.
+    if (handle == suggestions_query_) {
+      suggestions_query_ = 0;
+    } else if (handle == credit_cards_query_) {
+      credit_cards_query_ = 0;
+    } else if (handle == addresses_query_) {
+      addresses_query_ = 0;
+    } else {
+      NOTREACHED();
+    }
+
     CancelAllRequests();
     return;
   }
 
   const base::Time start = period_start_for_testing_.is_null()
                                ? GetPeriodStart()
                                : period_start_for_testing_;
 
   if (handle == suggestions_query_) {
     // Autocomplete suggestions.
@@ skipping 62 matching lines @@
                                                 ResultInt num_suggestions,
                                                 ResultInt num_credit_cards,
                                                 ResultInt num_addresses)
     : FinishedResult(source, num_suggestions),
       num_credit_cards_(num_credit_cards),
       num_addresses_(num_addresses) {}
 
 AutofillCounter::AutofillResult::~AutofillResult() {}
 
 }  // namespace browsing_data