Fix #1912: NRE in CSharpILMixedLanguage.MixedMethodBodyDisassembler.Disassemble()

ILSpy/Languages/CSharpILMixedLanguage.cs

@@ -91,7 +91,7 @@ namespace ICSharpCode.ILSpy
 					CSharpDecompiler decompiler = CreateDecompiler(module, options);
 					var st = decompiler.Decompile(handle);
 					WriteCode(csharpOutput, options.DecompilerSettings, st, decompiler.TypeSystem);
-					var mapping = decompiler.CreateSequencePoints(st).FirstOrDefault(kvp => (kvp.Key.MoveNextMethod ?? kvp.Key.Method).MetadataToken == handle);
+					var mapping = decompiler.CreateSequencePoints(st).FirstOrDefault(kvp => (kvp.Key.MoveNextMethod ?? kvp.Key.Method)?.MetadataToken == handle);
 					this.sequencePoints = mapping.Value ?? (IList<SequencePoint>)EmptyList<SequencePoint>.Instance;
 					this.codeLines = csharpOutput.ToString().Split(new[] { Environment.NewLine }, StringSplitOptions.None);
 					base.Disassemble(module, handle);