Remove DCHECKs that no longer reflect reality.

components/metrics/metrics_state_manager.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 "components/metrics/metrics_state_manager.h"
 
 #include "base/command_line.h"
 #include "base/guid.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/sparse_histogram.h"
@@ skipping 143 matching lines @@
   // entropy source.
   // This has two useful properties:
   //  1) It makes the entropy source less identifiable for parties that do not
   //     know the low entropy source.
   //  2) It makes the final entropy source resettable.
   const int low_entropy_source_value = GetLowEntropySource();
   UMA_HISTOGRAM_SPARSE_SLOWLY("UMA.LowEntropySourceValue",
                               low_entropy_source_value);
   if (IsMetricsReportingEnabled()) {
     if (entropy_source_returned_ == ENTROPY_SOURCE_NONE)
       entropy_source_returned_ = ENTROPY_SOURCE_HIGH;

[Ilya Sherman, 2014/08/19 21:04:14]

Is this if stmt, as well as the one below, still correct?

[Alexei Svitkine (slow), 2014/08/19 21:10:25]

Yes, the field is documented to track the first value returned.

-    DCHECK_EQ(ENTROPY_SOURCE_HIGH, entropy_source_returned_);
     const std::string high_entropy_source =
         client_id_ + base::IntToString(low_entropy_source_value);
     return scoped_ptr<const base::FieldTrial::EntropyProvider>(
         new SHA1EntropyProvider(high_entropy_source));
   }
 
   if (entropy_source_returned_ == ENTROPY_SOURCE_NONE)
     entropy_source_returned_ = ENTROPY_SOURCE_LOW;
-  DCHECK_EQ(ENTROPY_SOURCE_LOW, entropy_source_returned_);
 
 #if defined(OS_ANDROID) || defined(OS_IOS)
   return scoped_ptr<const base::FieldTrial::EntropyProvider>(
       new CachingPermutedEntropyProvider(local_state_,
                                          low_entropy_source_value,
                                          kMaxLowEntropySize));
 #else
   return scoped_ptr<const base::FieldTrial::EntropyProvider>(
       new PermutedEntropyProvider(low_entropy_source_value,
                                   kMaxLowEntropySize));
@@ skipping 119 matching lines @@
 
   local_state_->ClearPref(prefs::kMetricsClientID);
   local_state_->ClearPref(prefs::kMetricsLowEntropySource);
   local_state_->ClearPref(prefs::kMetricsResetIds);
 
   // Also clear the backed up client info.
   store_client_info_.Run(ClientInfo());
 }
 
 }  // namespace metrics