Define a mtr_t::start() wrapper inline.

storage/innobase/include/mtr0mtr.h

@@ -239,7 +239,10 @@ struct mtr_t {
 	/** Start a mini-transaction.
 	@param sync		true if it is a synchronous mini-transaction
 	@param read_only	true if read only mini-transaction */
-	void start(bool sync = true, bool read_only = false);
+	void start(bool sync = true, bool read_only = false)
+	{
+		start(NULL, sync, read_only);
+	}
 
 	/** Start a mini-transaction.
 	@param sync		true if it is a synchronous mini-transaction

storage/innobase/mtr/mtr0mtr.cc

@@ -491,15 +491,6 @@ mtr_write_log(
 	log_close();
 }
 
-/** Start a mini-transaction.
-@param sync		true if it is a synchronous mini-transaction
-@param read_only	true if read only mini-transaction */
-void
-mtr_t::start(bool sync, bool read_only)
-{
-	start(NULL, sync, read_only);
-}
-
 /** Start a mini-transaction.
 @param sync		true if it is a synchronous mini-transaction
 @param read_only	true if read only mini-transaction */