Copy & paste of "invalid" table cell selection is broken

[jodator]

This error occurs also when coping a table section that will result in broken table layout to the clipboard. I think that one fix could be addressed in two places (both when copying to the clipboard and getting table from the clipboard).

This returns only number of tableRow elements and when there are spans then this get's completely messed up eg:

+----+----+
| 00 | 01 |
+    +    +
|    |    |
+    +----+
|    | 11 |
+    +    +
|    |    |
+----+----+

for table above (such layout can be copied from bigger table) tableUtils.getRows() will return 2 but:

• cell 00 has rowspan = 4
• cell 01 and 11 has rowspan = 2 

I think we should use real table height.

Originally posted by @niegowski in #7226