service worker: Add CHECKs for investigating null http info bug.

content/browser/service_worker/service_worker_url_request_job.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 "content/browser/service_worker/service_worker_url_request_job.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <map>
@@ skipping 569 matching lines @@
     ServiceWorkerMetrics::RecordFallbackedRequestMode(request_mode_);
     if (IsFallbackToRendererNeeded()) {
       FinalizeFallbackToRenderer();
     } else {
       FinalizeFallbackToNetwork();
     }
     return;
   }
 
   // We should have a response now.
-  DCHECK_EQ(SERVICE_WORKER_FETCH_EVENT_RESULT_RESPONSE, fetch_result);
+  // TODO(falken): Turn to DCHECK once https://crbug.com/485900 is resolved.
+  CHECK_EQ(SERVICE_WORKER_FETCH_EVENT_RESULT_RESPONSE, fetch_result);
 
   // A response with status code 0 is Blink telling us to respond with network
   // error.
   if (response.status_code == 0) {
     RecordStatusZeroResponseError(response.error);
     NotifyStartError(
         net::URLRequestStatus(net::URLRequestStatus::FAILED, net::ERR_FAILED));
     return;
   }
 
   load_timing_info_.send_end = base::TimeTicks::Now();
 
   // Creates a new HttpResponseInfo using the the ServiceWorker script's
   // HttpResponseInfo to show HTTPS padlock.
   // TODO(horo): When we support mixed-content (HTTP) no-cors requests from a
   // ServiceWorker, we have to check the security level of the responses.
   DCHECK(!http_response_info_);
   DCHECK(version);
   const net::HttpResponseInfo* main_script_http_info =
       version->GetMainScriptHttpResponseInfo();
+  CHECK(main_script_http_info);
   if (main_script_http_info) {
     // In normal case |main_script_http_info| must be set while starting the
     // ServiceWorker. But when the ServiceWorker registration database was not
     // written correctly, it may be null.
     // TODO(horo): Change this line to DCHECK when crbug.com/485900 is fixed.
     http_response_info_.reset(
         new net::HttpResponseInfo(*main_script_http_info));
   }
 
   // Set up a request for reading the stream.
@@ skipping 239 matching lines @@
       base::Bind(&ServiceWorkerURLRequestJob::DidPrepareFetchEvent,
                  weak_factory_.GetWeakPtr(), active_worker),
       base::Bind(&ServiceWorkerURLRequestJob::DidDispatchFetchEvent,
                  weak_factory_.GetWeakPtr())));
   worker_start_time_ = base::TimeTicks::Now();
   fetch_dispatcher_->MaybeStartNavigationPreload(request());
   fetch_dispatcher_->Run();
 }
 
 }  // namespace content