Document new constructor for Windows.UI.Xaml.LayoutCycleException (dotnet#2983)

Not owned by my immediate team, but I figured it would be quick to document. It's the only undoc API in this namespace.

Based on this:

https://docs.microsoft.com/en-us/dotnet/api/system.exception.-ctor?view=netcore-3.0#System_Exception__ctor_System_Runtime_Serialization_SerializationInfo_System_Runtime_Serialization_StreamingContext_

Author: carlossanlop

xml/Windows.UI.Xaml/LayoutCycleException.xml

@@ -80,9 +80,9 @@
         <Parameter Name="streamingContext" Type="System.Runtime.Serialization.StreamingContext" Index="1" FrameworkAlternate="dotnet-plat-ext-3.0" />
       </Parameters>
       <Docs>
-        <param name="serializationInfo">To be added.</param>
-        <param name="streamingContext">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="serializationInfo">The <see cref="T:System.Runtime.Serialization.SerializationInfo" /> that holds the serialized object data about the exception being thrown.</param>
+        <param name="streamingContext">The <see cref="T:System.Runtime.Serialization.StreamingContext" /> that contains contextual information about the source or destination.</param>
+        <summary>Initializes a new instance of the <see cref="T:Windows.UI.Xaml.LayoutCycleException" /> class with serialized data.</summary>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -111,4 +111,4 @@
       </Docs>
     </Member>
   </Members>
-</Type>
+</Type>