Issue 113806

1. Create a new spreadsheet
2. Enter a few values in columns A and B
   example:
   1   1
   2   2
   3   3
   4   4

3. Enter this formula in cell C1:
   =A1 + A2
4. Fill the formula in C1 down to C4
5. Select all cells, right-click, "Format Cells...", disable cell protection
6. Select all cells in column C, "Format Cells...", enable cell protection
7. "Protect Sheet", enter password (or none)
8. Confirm cell protection by attempting to type into cell C1 (works)
9. Select cells A1 - B1, drag cell both cells to below line 4

RESULT:   Formula in C1 has changed to accommodate the relocated cells.
EXPECTED: Formula in C1 is protected from alteration, either by allowing the
drag-and-drop operation and ignoring the formula change, prohibiting the
drag-and-drop operation, or (my preference) alerting the user of the situation
and offering them the previous two choices.

This "trick" could be used to subvert the protection of a cell formula to use
data that is hidden elsewhere on the sheet (in my example, cells A6-B6, which is
where I dropped the two cells I moved), while presenting false data in the
expected data location (cells A1 - B1).

Although it is trivial to verify that the formulas are pointing to alternative
locations for a single cell, verifying many formulas in a complex spreadsheet is
not reasonable and I believe this problem should be fixed for this reason.