Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

mcs/class/corlib/ReferenceSources/BCLDebug.cs

@@ -0,0 +1,45 @@
+using System.Diagnostics;
+
+namespace System
+{
+    internal enum LogLevel {
+        Trace  = 0,
+        Status = 20,
+        Warning= 40,
+        Error  = 50,
+        Panic  = 100,
+    }
+
+	static class BCLDebug
+	{
+		[Conditional("_DEBUG")]
+		static public void Assert(bool condition, string message)
+		{
+		}
+
+		[Conditional("_DEBUG")]
+		internal static void Correctness(bool expr, string msg)
+		{
+		}
+
+		[Conditional("_DEBUG")]
+		static public void Log (string message)
+		{
+		}
+
+		[Conditional("_DEBUG")]
+		static public void Log (string switchName, string message)
+		{
+		}
+
+		[Conditional("_DEBUG")]
+		public static void Log (string switchName, LogLevel level, params object[] messages)
+		{
+		}
+
+		[Conditional("_DEBUG")]
+		internal static void Perf (bool expr, string msg)
+		{
+		}
+	}
+}