Revert of Collect information about failing histogram factory calls.

base/metrics/statistics_recorder.cc

Index: base/metrics/statistics_recorder.cc
diff --git a/base/metrics/statistics_recorder.cc b/base/metrics/statistics_recorder.cc
index 90d64bb9ea3c6bf3a1b351f3d494d9c534dc7d48..d0fa2add3603b3f574dfa9ef9e5ee2e6b152aafc 100644
--- a/base/metrics/statistics_recorder.cc
+++ b/base/metrics/statistics_recorder.cc
@@ -5,7 +5,6 @@
 #include "base/metrics/statistics_recorder.h"
 
 #include "base/at_exit.h"
-#include "base/debug/alias.h"
 #include "base/debug/leak_annotations.h"
 #include "base/json/string_escape.h"
 #include "base/logging.h"
@@ -124,17 +123,13 @@
         histogram_to_return = histogram;
       } else {
         // We already have one histogram with this name.
-        CHECK_EQ(histogram->histogram_name(),
-                 it->second->histogram_name()) << "hash collision";
+        DCHECK_EQ(histogram->histogram_name(),
+                  it->second->histogram_name()) << "hash collision";
         histogram_to_return = it->second;
         histogram_to_delete = histogram;
       }
-      base::debug::Alias(&it);
-      base::debug::Alias(&name);
-      base::debug::Alias(&name_hash);
     }
   }
-  base::debug::Alias(&histogram);
   delete histogram_to_delete;
   return histogram_to_return;
 }
@@ -284,22 +279,10 @@
   if (histograms_ == NULL)
     return NULL;
 
-  const uint64_t lookup_hash = HashMetricName(name);
-  HistogramMap::iterator it = histograms_->find(lookup_hash);
+  HistogramMap::iterator it = histograms_->find(HashMetricName(name));
   if (histograms_->end() == it)
     return NULL;
-
-  const uint64_t existing_hash = it->first;
-  const char* existing_name = it->second->histogram_name().c_str();
-  HistogramMap* histograms = histograms_;
-  CHECK_EQ(name, it->second->histogram_name()) << "hash collision";
-  base::debug::Alias(&lookup_hash);
-  base::debug::Alias(&existing_hash);
-  base::debug::Alias(&name);
-  base::debug::Alias(&existing_name);
-  base::debug::Alias(&it);
-  base::debug::Alias(&histograms);
-
+  DCHECK_EQ(name, it->second->histogram_name()) << "hash collision";
   return it->second;
 }