Add assert() statements on the nExtraDelete variable in vdbe.c to try to verify

that the FORDELETE and IDXDELETE flags are being generated correctly.  Those
flags are not currently generated correctly, and so the assert()s trip on this
check-in.

FossilOrigin-Name: dde1db0dd2e2cf04706117629756c352b178ebb8

src/vdbeInt.h

@@ -82,6 +82,7 @@ struct VdbeCursor {
   u8 isTable;           /* True for rowid tables.  False for indexes */
 #ifdef SQLITE_DEBUG
   u8 seekOp;            /* Most recent seek operation on this cursor */
+  u8 wrFlag;            /* The wrFlag argument to sqlite3BtreeCursor() */
 #endif
   Bool isEphemeral:1;   /* True for an ephemeral table */
   Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */