Notify GCMAppHandlers when the store is reset, so they clear cached IDs

chrome/browser/push_messaging/push_messaging_app_identifier.cc

 // Copyright 2014 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/push_messaging/push_messaging_app_identifier.h"
 
 #include <string.h>
 
 #include "base/guid.h"
 #include "base/logging.h"
@@ skipping 142 matching lines @@
       profile->GetPrefs()->GetDictionary(prefs::kPushMessagingAppIdentifierMap);
   for (auto it = base::DictionaryValue::Iterator(*map); !it.IsAtEnd();
        it.Advance()) {
     result.push_back(FindByAppId(profile, it.key()));
   }
 
   return result;
 }
 
 // static
+void PushMessagingAppIdentifier::DeleteAllFromPrefs(Profile* profile) {
+  DictionaryPrefUpdate update(profile->GetPrefs(),
+                              prefs::kPushMessagingAppIdentifierMap);
+  base::DictionaryValue* map = update.Get();
+  map->Clear();
+}
+
+// static
 size_t PushMessagingAppIdentifier::GetCount(Profile* profile) {
   return profile->GetPrefs()
       ->GetDictionary(prefs::kPushMessagingAppIdentifierMap)
       ->size();
 }
 
 PushMessagingAppIdentifier::PushMessagingAppIdentifier()
     : origin_(GURL::EmptyGURL()), service_worker_registration_id_(-1) {}
 
 PushMessagingAppIdentifier::PushMessagingAppIdentifier(
@@ skipping 62 matching lines @@
   if (UseInstanceID(app_id_)) {
     DCHECK(!base::IsValidGUID(guid));
 
     // Replace suffix with valid hex so we can validate the rest of the string.
     guid = guid.replace(guid.size() - kGuidSuffixLength, kGuidSuffixLength,
                         kGuidSuffixLength, 'C');
   }
   DCHECK(base::IsValidGUID(guid));
 #endif  // DCHECK_IS_ON()
 }