Fix scan coverity issues:

CID 184299:  Null pointer dereferences  (FORWARD_NULL)
CID 184297:  Error handling issues  (UNCAUGHT_EXCEPT)
CID 184296:  Uninitialized members  (UNINIT_CTOR)
CID 184292:  Uninitialized members  (UNINIT_CTOR)

src/Mod/Drawing/Gui/TaskOrthoViews.cpp

@@ -314,7 +314,11 @@ OrthoViews::~OrthoViews()
     for (int i = views.size() - 1; i >= 0; i--)
         delete views[i];
 
-    page->recomputeFeature();
+    try {
+        page->recomputeFeature();
+    }
+    catch (...) {
+    }
 }
 
 void OrthoViews::slotDeletedDocument(const App::Document& Obj)

src/Mod/Path/libarea/Adaptive.cpp

@@ -155,6 +155,10 @@ class BoundBox
   public:
 	BoundBox()
 	{
+		minX = 0;
+		maxX = 0;
+		minY = 0;
+		maxY = 0;
 	}
 
 	// generic: first point
@@ -407,7 +411,7 @@ void CleanPath(const Path &inp, Path &outpt, double tolerance)
 	long index;
 	for (long i = 0; i < size; i++)
 	{
-		index = clpSegmentIndex + i;
+		index = static_cast<long>(clpSegmentIndex + i);
 		if (index >= size) index -= size;
 		outpt.push_back(tmp.at(index));
 	}
@@ -842,6 +846,7 @@ class PerfCounter
 		name = p_name;
 		count = 0;
 		running = false;
+		start_ticks = 0;
 		total_ticks = 0;
 	}
 	inline void Start()

src/Mod/Spreadsheet/Gui/SheetTableView.cpp

@@ -347,7 +347,7 @@ bool SheetTableView::event(QEvent *event)
             return true;
         }
     }
-    else if (event->type() == QEvent::ShortcutOverride) {
+    else if (event && event->type() == QEvent::ShortcutOverride) {
         QKeyEvent * kevent = static_cast<QKeyEvent*>(event);
         if (kevent->modifiers() == Qt::NoModifier ||
             kevent->modifiers() == Qt::ShiftModifier ||