Convert to SQLite amalgamation.

third_party/sqlite/src/src/sqlite3ext.h

 /*
 ** 2006 June 7
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
 **
 **    May you do good and not evil.
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
@@ skipping 354 matching lines @@
 #define sqlite3_result_zeroblob        sqlite3_api->result_zeroblob
 #define sqlite3_result_error_code      sqlite3_api->result_error_code
 #define sqlite3_test_control           sqlite3_api->test_control
 #define sqlite3_randomness             sqlite3_api->randomness
 #define sqlite3_context_db_handle      sqlite3_api->context_db_handle
 #define sqlite3_extended_result_codes  sqlite3_api->extended_result_codes
 #define sqlite3_limit                  sqlite3_api->limit
 #define sqlite3_next_stmt              sqlite3_api->next_stmt
 #define sqlite3_sql                    sqlite3_api->sql
 #define sqlite3_status                 sqlite3_api->status
+#endif /* SQLITE_CORE */
 
 #define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api = 0;
 #define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;
 
-#else
-
-#define SQLITE_EXTENSION_INIT1
-#define SQLITE_EXTENSION_INIT2(v)
-
-#endif /* SQLITE_CORE */
-
 #endif /* _SQLITE3EXT_H_ */