[System.Drawing] Fix cut & paste error (dotnet/corefx#37788)

Commit migrated from https://github.com/dotnet/corefx/commit/8261325d82e18ce559dd19cde7e40c2ab140ed8b

diff --git a/src/libraries/System.Drawing.Common/src/System/Drawing/Pen.cs b/src/libraries/System.Drawing.Common/src/System/Drawing/Pen.cs
index b8e7250972597f83ce8d0fb2fccb2d723c799d8f..d6077812f5472c313c2b5fa600ec4d80beb1dded 100644 (file)
--- a/src/libraries/System.Drawing.Common/src/System/Drawing/Pen.cs
+++ b/src/libraries/System.Drawing.Common/src/System/Drawing/Pen.cs
@@ -148,7 +148,7 @@ namespace System.Drawing
             }
             else if (_immutable)
             {
-                throw new ArgumentException(SR.Format(SR.CantChangeImmutableObjects, nameof(Brush)));
+                throw new ArgumentException(SR.Format(SR.CantChangeImmutableObjects, nameof(Pen)));
             }
 
             if (_nativePen != IntPtr.Zero)