[BackgroundSync] Remove dead code

This is leftover from previous cleanup work to remove the
registration id. This corruption checker checked to make sure
that the registration id was valid, but since the id is gone
the corruption checker should go as well.

Change-Id: I226e2ac388c2163d12ad6dbfe8edb95b3682b7fd
Reviewed-on: https://chromium-review.googlesource.com/c/1319690Reviewed-by: Peter Beverloo <peter@chromium.org>
Commit-Queue: Josh Karlin <jkarlin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605726}

content/browser/background_sync/background_sync_manager.cc

@@ -382,7 +382,6 @@ void BackgroundSyncManager::InitDidGetDataFromBackend(
     return;
   }
 
-  bool corruption_detected = false;
   for (const std::pair<int64_t, std::string>& data : user_data) {
     BackgroundSyncRegistrationsProto registrations_proto;
     if (registrations_proto.ParseFromString(data.second)) {
@@ -406,19 +405,9 @@ void BackgroundSyncManager::InitDidGetDataFromBackend(
             base::Time::FromInternalValue(registration_proto.delay_until()));
       }
     }
-
-    if (corruption_detected)
-      break;
-  }
-
-  if (corruption_detected) {
-    LOG(ERROR) << "Corruption detected in background sync backend";
-    DisableAndClearManager(std::move(callback));
-    return;
   }
 
   FireReadyEvents();
-
   base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, std::move(callback));
 }