Remove another instance of a dcheck when 'begin' is set incorrectly.

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 "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/time.h"
@@ skipping 238 matching lines @@
   if (!first_paint.is_null()) {
     // 'first_paint' can be before 'begin' for an unknown reason.
     // See bug http://crbug.com/125273 for details.
     if (begin <= first_paint) {
       PLT_HISTOGRAM("PLT.BeginToFirstPaint", first_paint - begin);
     }
     DCHECK(commit <= first_paint);
     PLT_HISTOGRAM("PLT.CommitToFirstPaint", first_paint - commit);
   }
   if (!first_paint_after_load.is_null()) {
-    DCHECK(begin <= first_paint_after_load);
-    PLT_HISTOGRAM("PLT.BeginToFirstPaintAfterLoad",
-      first_paint_after_load - begin);
+    // 'first_paint_after_load' can be before 'begin' for an unknown reason.
+    // See bug http://crbug.com/125273 for details.
+    if (begin <= first_paint_after_load) {
+      PLT_HISTOGRAM("PLT.BeginToFirstPaintAfterLoad",
+          first_paint_after_load - begin);
+    }
     DCHECK(commit <= first_paint_after_load);
     PLT_HISTOGRAM("PLT.CommitToFirstPaintAfterLoad",
         first_paint_after_load - commit);
     DCHECK(finish_all_loads <= first_paint_after_load);
     PLT_HISTOGRAM("PLT.FinishToFirstPaintAfterLoad",
         first_paint_after_load - finish_all_loads);
   }
   PLT_HISTOGRAM("PLT.BeginToFinishDoc", begin_to_finish_doc);
   PLT_HISTOGRAM("PLT.BeginToFinish", begin_to_finish_all_loads);
 
@@ skipping 697 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();
 }