Dispatch DRP IPC call from renderer main thread

chrome/renderer/page_load_histograms.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/renderer/page_load_histograms.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 863 matching lines @@
   URLPattern::SchemeMasks scheme_type =
       GetSupportedSchemeType(frame->document().url());
 
   DocumentState* document_state =
       DocumentState::FromDataSource(frame->dataSource());
 
   bool data_reduction_proxy_was_used = false;
   data_reduction_proxy::LoFiStatus lofi_status =
       data_reduction_proxy::LOFI_STATUS_TEMPORARILY_OFF;
   if (!document_state->proxy_server().IsEmpty()) {
-    Send(new DataReductionProxyViewHostMsg_DataReductionProxyStatus(
-        document_state->proxy_server(), &data_reduction_proxy_was_used,
-        &lofi_status));
+    bool handled =
+        Send(new DataReductionProxyViewHostMsg_DataReductionProxyStatus(
+            document_state->proxy_server(), &data_reduction_proxy_was_used,
+            &lofi_status));
+    // If the IPC call is not handled, then |data_reduction_proxy_was_used|
+    // should remain |false|.
+    DCHECK(handled || !data_reduction_proxy_was_used);
   }
 
   bool came_from_websearch =
       IsFromGoogleSearchResult(frame->document().url(),
                                GURL(frame->document().referrer()));
   int websearch_chrome_joint_experiment_id = kNoExperiment;
   bool is_preview = false;
   if (came_from_websearch) {
     websearch_chrome_joint_experiment_id =
         GetQueryStringBasedExperiment(GURL(frame->document().referrer()));
@@ skipping 119 matching lines @@
 
   DCHECK(document_state);
   DCHECK(ds);
   GURL url(ds->request().url());
   Time start = document_state->start_load_time();
   Time finish = document_state->finish_load_time();
   // TODO(mbelshe): should we log more stats?
   VLOG(1) << "PLT: " << (finish - start).InMilliseconds() << "ms "
           << url.spec();
 }