Remove explicit keyword from multi-argument constructors

net/disk_cache/stats_histogram.h

Index: net/disk_cache/stats_histogram.h
diff --git a/net/disk_cache/stats_histogram.h b/net/disk_cache/stats_histogram.h
index f41c384722c17e7f5cab8252b0030600c314395c..318a8bce77483bec4292dde7a2dd3aff139b13dc 100644
--- a/net/disk_cache/stats_histogram.h
+++ b/net/disk_cache/stats_histogram.h
@@ -30,8 +30,8 @@ class StatsHistogram : public base::Histogram {
     }
   };
 
-  explicit StatsHistogram(const std::string& name, Sample minimum,
-                          Sample maximum, size_t bucket_count)
+  StatsHistogram(const std::string& name, Sample minimum,
+                 Sample maximum, size_t bucket_count)
       : Histogram(name, minimum, maximum, bucket_count), init_(false) {}
   virtual ~StatsHistogram();