SAFE_POINT on enzyme disabling/enabling

Scenario:

1. Open example.gb
2. Click "Find restriction enzymes"
3. Choose "Tth111I"
4. Click OK
5. Open details view.
6. Select Tth111I site in Restriction Sites Map and expand it
7. Select Disable "Tth111I" highligting
   Expected: No highligting
8. Expand context menu again and select Enable "Tth111I" highligting

SAFE_POINT:
Trying to recover from error: Annotation has been already added at D:\ugene\src\corelibs\U2View\src\ov_sequence\PanViewRows.cpp:87

Another scenario:

1. Load example/GenBank/sars.gb
2. Select Show Restricted Sites option
3. Expand Option panel and select Annotation Highlighting section
4. Click on BamHI enzyme
   SAFE_POINT:
   mouse_press <no active modal> Left_button 1161 245 CLASS_NAME: U2::AnnotHighlightTree TREE_ITEM: BamHI OBJECT_NAME: OP_ANNOT_HIGHLIGHT_TREE
   Trying to recover from error: Annotation has been already added at D:\ugene\src\corelibs\U2View\src\ov_sequence\PanViewRows.cpp:87