Make URLRequestThrottlerEntryInterface inherit RefCountedThreadSafe,

net/url_request/url_request_throttler_entry_interface.h

Index: net/url_request/url_request_throttler_entry_interface.h
diff --git a/net/url_request/url_request_throttler_entry_interface.h b/net/url_request/url_request_throttler_entry_interface.h
index 616e1d0dcd5fa6f1e9f4087f9e90f1403fa9d111..f443b2934b94b3bb7265d78f66028696c92a523d 100644
--- a/net/url_request/url_request_throttler_entry_interface.h
+++ b/net/url_request/url_request_throttler_entry_interface.h
@@ -15,7 +15,7 @@ class URLRequestThrottlerHeaderInterface;
 
 // Interface provided on entries of the URL request throttler manager.
 class URLRequestThrottlerEntryInterface
-    : public base::RefCounted<URLRequestThrottlerEntryInterface> {
+    : public base::RefCountedThreadSafe<URLRequestThrottlerEntryInterface> {
  public:
   URLRequestThrottlerEntryInterface() {}
 
@@ -51,6 +51,7 @@ class URLRequestThrottlerEntryInterface
   virtual void ReceivedContentWasMalformed() = 0;
 
  protected:
+  friend class base::RefCountedThreadSafe<URLRequestThrottlerEntryInterface>;
   virtual ~URLRequestThrottlerEntryInterface() {}
 
  private: