[IE] Failed to restore collapsed selection from editor blured

[Garry Yao]

Restore selection doesn't work for collapsed range might be caused by a IE bug, which make all commands unable to apply on the right place.

Procedures

1. Anchor the selection in a single point with offsets in document;
2. Click anywhere outside the editor chrome;
3. Perform e.g. the Anchor command;
4. Expected result:
   
   • The command dialog opened;
   • Javascript Error occurs;