[656150] Fix repl recovery after invalid expression.

mcs/mcs/eval.cs

@@ -243,6 +243,8 @@ namespace Mono.CSharp
 			lock (evaluator_lock){
 				if (!inited)
 					Init ();
+				else
+					ctx.Report.Printer.Reset ();
 
 			//	RootContext.ToplevelTypes = new ModuleContainer (ctx);
 

mcs/mcs/report.cs

@@ -657,6 +657,12 @@ namespace Mono.CSharp {
 					output.WriteLine (s + msg.MessageType + ")");
 			}
 		}
+
+		public void Reset ()
+		{
+			// Temporary hack for broken repl flow
+			errors = warnings = 0;
+		}
 	}
 
 	//