fix stepping in inner types

Debugger/ILSpy.Debugger/Services/Debugger/WindowsDebugger.cs

@@ -306,13 +306,15 @@ namespace ILSpy.Debugger.Services
 			StackFrame frame;
 			var map = GetCurrentCodeMapping(out frame, out isMatch);
 			if (map == null) {
-				return debuggedProcess.SelectedThread.MostRecentStackFrame;
+				frame = debuggedProcess.SelectedThread.MostRecentStackFrame;
+				frame.ILRanges = new [] { 0, 1 };
 			} else {
 				//var frame = debuggedProcess.SelectedThread.MostRecentStackFrame;
 				frame.SourceCodeLine = map.SourceCodeLine;
 				frame.ILRanges = map.ToArray(isMatch);
-				return frame;
 			}
+			
+			return frame;
 		}
 		
 		public void StepInto()
@@ -817,7 +819,8 @@ namespace ILSpy.Debugger.Services
 				int line;
 				TypeDefinition type;
 				
-				if (CodeMappingsStorage.GetSourceCodeFromMetadataTokenAndOffset(frame.MethodInfo.DeclaringType.FullName, token, ilOffset, out type, out line)) {
+				if (CodeMappingsStorage.GetSourceCodeFromMetadataTokenAndOffset(frame.MethodInfo.DeclaringType.FullName, token, ilOffset, out type, out line) 
+				    && type.DeclaringType == null) {
 					DebuggerService.RemoveCurrentLineMarker();
 					DebuggerService.JumpToCurrentLine(type, line, 0, line, 0);
 				} else {