First patch in making destructors of refcounted objects private.

app/sql/connection.h

Index: app/sql/connection.h
===================================================================
--- app/sql/connection.h	(revision 30973)
+++ app/sql/connection.h	(working copy)
@@ -76,7 +76,6 @@
 // corruption, low-level IO errors or locking violations.
 class ErrorDelegate : public base::RefCounted<ErrorDelegate> {
  public:
-  virtual ~ErrorDelegate() {}
   // |error| is an sqlite result code as seen in sqlite\preprocessed\sqlite3.h
   // |connection| is db connection where the error happened and |stmt| is
   // our best guess at the statement that triggered the error.  Do not store
@@ -89,6 +88,11 @@
   // re-tried then returning SQLITE_OK is appropiate; otherwise is recomended
   // that you return the original |error| or the appropiae error code.
   virtual int OnError(int error, Connection* connection, Statement* stmt) = 0;
+
+ protected:
+  friend class base::RefCounted<ErrorDelegate>;
+
+  virtual ~ErrorDelegate() {}
 };
 
 class Connection {
@@ -286,7 +290,6 @@
     // Default constructor initializes to an invalid statement.
     StatementRef();
     StatementRef(Connection* connection, sqlite3_stmt* stmt);
-    ~StatementRef();
 
     // When true, the statement can be used.
     bool is_valid() const { return !!stmt_; }
@@ -304,6 +307,10 @@
     void Close();
 
    private:
+    friend class base::RefCounted<StatementRef>;
+
+    ~StatementRef();
+
     Connection* connection_;
     sqlite3_stmt* stmt_;