Fixed conditional breakpoints for statements that do not return bool

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@5308 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/AddIns/Debugger/Debugger.AddIn/Service/WindowsDebugger.cs

@@ -604,7 +604,7 @@ namespace ICSharpCode.SharpDevelop.Services
 				SupportedLanguage supportedLanguage = (SupportedLanguage)Enum.Parse(typeof(SupportedLanguage), language, true);
 				Value val = ExpressionEvaluator.Evaluate(code, supportedLanguage, debuggedProcess.SelectedStackFrame);
 				
-				if (val.PrimitiveValue is bool)
+				if (val != null && val.Type.IsPrimitive && val.PrimitiveValue is bool)
 					return (bool)val.PrimitiveValue;
 				else
 					return false;