SCAYT breaks undo system

[Garry Yao]

Reproducing Procedures

1. Open 'replacebyclass' sample page;
2. Enable 'SCAYT' and wait for SCAYT to be activiated;
3. Put cursor inside the word 'sample' as following:

   sam^ple
   

4. Open 'Smiley' dialog to insert one default icon at the cursor position;
5. Wait until the SCAYT has finished marking the mis-spelled word 'sam' and 'ple' respectively;
6. Press 'Undo' button to revert the smiley insertion;
   • Actual Result: The SCAYT mark line was reverted but not the smiley icon.
   • Expected Result: Both smiley icon insertion and SCAYT mark get reverted.

[Garry Yao]

Note that there're two problems involved here:

1. First of all, SCAYT should refresh after undo;
2. Second, SCAYT has to notify our undo system of the newly added SCAYT word markers.

[WebSpellChecker.net]

SCAYT instance status check was added ( was led to error whet text source edit )

[Garry Yao]

Fixed with [5485] with dead code blocks removed.

[Alfonso Martínez de Lizarrondo]

This has broken the undo system if there is no instance named "editor1" #5685