Move ErrorDelegate to its own file and add static utility functions to ErrorDelegate

sql/connection.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SQL_CONNECTION_H_
 #define SQL_CONNECTION_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 65 matching lines @@
 // ErrorDelegate defines the interface to implement error handling and recovery
 // for sqlite operations. This allows the rest of the classes to return true or
 // false while the actual error code and causing statement are delivered using
 // the OnError() callback.
 // The tipical usage is to centralize the code designed to handle database
 // corruption, low-level IO errors or locking violations.
 class SQL_EXPORT 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
-  // these pointers.
+  // |error| is an sqlite result code as seen in sqlite3.h. |connection| is the
+  // db connection where the error happened and |stmt| is our best guess at the
+  // statement that triggered the error. Do not store these pointers.
   //
   // |stmt| MAY BE NULL if there is no statement causing the problem (i.e. on
   // initialization).
   //
-  // If the error condition has been fixed an the original statement succesfuly
-  // re-tried then returning SQLITE_OK is appropiate; otherwise is recomended
-  // that you return the original |error| or the appropiae error code.
+  // If the error condition has been fixed and the original statement succesfuly
+  // re-tried then returning SQLITE_OK is appropriate; otherwise it is
+  // recommended that you return the original |error| or the appropriate error
+  // code.
   virtual int OnError(int error, Connection* connection, Statement* stmt) = 0;
 };
 
 class SQL_EXPORT Connection {
  private:
   class StatementRef;  // Forward declaration, see real one below.
 
  public:
   // The database is opened by calling Open[InMemory](). Any uncommitted
   // transactions will be rolled back when this object is deleted.
@@ skipping 336 matching lines @@
   // This object handles errors resulting from all forms of executing sqlite
   // commands or statements. It can be null which means default handling.
   scoped_ptr<ErrorDelegate> error_delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(Connection);
 };
 
 }  // namespace sql
 
 #endif  // SQL_CONNECTION_H_