Don't crash debug builds for full allocator.

base/metrics/persistent_histogram_allocator.cc

 // Copyright 2016 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 "base/metrics/persistent_histogram_allocator.h"
 
 #include <memory>
 
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ skipping 385 matching lines @@
   CreateHistogramResultType result;
   if (memory_allocator_->IsCorrupt()) {
     RecordCreateHistogramResult(CREATE_HISTOGRAM_ALLOCATOR_NEWLY_CORRUPT);
     result = CREATE_HISTOGRAM_ALLOCATOR_CORRUPT;
   } else if (memory_allocator_->IsFull()) {
     result = CREATE_HISTOGRAM_ALLOCATOR_FULL;
   } else {
     result = CREATE_HISTOGRAM_ALLOCATOR_ERROR;
   }
   RecordCreateHistogramResult(result);
-  NOTREACHED() << "error=" << result;
+
+  // Crash for failures caused by internal bugs but not "full" which is
+  // dependent on outside code.
+  if (result != CREATE_HISTOGRAM_ALLOCATOR_FULL)
+    NOTREACHED() << memory_allocator_->Name() << ", error=" << result;
 
   return nullptr;
 }
 
 void PersistentHistogramAllocator::FinalizeHistogram(Reference ref,
                                                      bool registered) {
   if (registered) {
     // If the created persistent histogram was registered then it needs to
     // be marked as "iterable" in order to be found by other processes. This
     // happens only after the histogram is fully formed so it's impossible for
@@ skipping 515 matching lines @@
   while (true) {
     std::unique_ptr<HistogramBase> histogram =
         import_iterator_.GetNextWithIgnore(record_to_ignore);
     if (!histogram)
       break;
     StatisticsRecorder::RegisterOrDeleteDuplicate(histogram.release());
   }
 }
 
 }  // namespace base