Use string for Histogram names since these are all ASCII anyway wide-characte...

net/disk_cache/stats.cc

Index: net/disk_cache/stats.cc
===================================================================
--- net/disk_cache/stats.cc	(revision 10269)
+++ net/disk_cache/stats.cc	(working copy)
@@ -123,7 +123,7 @@
   if (!size_histogram_.get()) {
     // Stats may be reused when the cache is re-created, but we want only one
     // histogram at any given time.
-    size_histogram_.reset(new StatsHistogram(L"DiskCache.SizeStats"));
+    size_histogram_.reset(new StatsHistogram("DiskCache.SizeStats"));
     size_histogram_->Init(this);
   }
 
@@ -267,4 +267,3 @@
 }
 
 }  // namespace disk_cache
-