Add uma stats to help evaluate the impact of changes to the quota allocation logic.

content/browser/appcache/appcache_response.h

Index: content/browser/appcache/appcache_response.h
diff --git a/content/browser/appcache/appcache_response.h b/content/browser/appcache/appcache_response.h
index 47f33522475238740ab41df08b4eda977df1fd7a..86c7e1be8446aa29e1857d8b1727e58e4ed4eaa9 100644
--- a/content/browser/appcache/appcache_response.h
+++ b/content/browser/appcache/appcache_response.h
@@ -94,7 +94,8 @@ class CONTENT_EXPORT AppCacheDiskCacheInterface {
     virtual ~Entry() {}
   };
 
-  AppCacheDiskCacheInterface();
+  // The uma_name pointer must remain valid for the life of the object.
+  AppCacheDiskCacheInterface(const char* uma_name);
 
   virtual int CreateEntry(int64_t key,
                           Entry** entry,
@@ -105,11 +106,13 @@ class CONTENT_EXPORT AppCacheDiskCacheInterface {
   virtual int DoomEntry(int64_t key,
                         const net::CompletionCallback& callback) = 0;
 
+  const char* uma_name() const { return uma_name_; }
   base::WeakPtr<AppCacheDiskCacheInterface> GetWeakPtr();
 
  protected:
   virtual ~AppCacheDiskCacheInterface();
 
+  const char* uma_name_;
   base::WeakPtrFactory<AppCacheDiskCacheInterface> weak_factory_;
 };