Clarify EventLevel.LogAlways (dotnet#7924)

Author: noahfalk

xml/System.Diagnostics.Tracing/EventLevel.xml

@@ -223,7 +223,7 @@ The following example shows how to use the `Verbose` enumeration member to ident
       </ReturnValue>
       <MemberValue>0</MemberValue>
       <Docs>
-        <summary>No level filtering is done on the event.</summary>
+        <summary>No level filtering is done on the event. When used as a level filter for enabling events, for example in EventListener.EnableEvents(), events of all levels will be included.</summary>
       </Docs>
     </Member>
     <Member MemberName="Verbose">

xml/System.Diagnostics.Tracing/EventListener.xml

@@ -267,7 +267,7 @@
       </Parameters>
       <Docs>
         <param name="eventSource">The event source to enable events for.</param>
-        <param name="level">The level of events to enable.</param>
+        <param name="level">The level of events to enable. Using EventLevel.LogAlways includes events of all levels.</param>
         <summary>Enables events for the specified event source that has the specified verbosity level or lower.</summary>
         <remarks>
         </remarks>
@@ -314,7 +314,7 @@
       </Parameters>
       <Docs>
         <param name="eventSource">The event source to enable events for.</param>
-        <param name="level">The level of events to enable.</param>
+        <param name="level">The level of events to enable. Using EventLevel.LogAlways includes events of all levels.</param>
         <param name="matchAnyKeyword">The keyword flags necessary to enable the events.</param>
         <summary>Enables events for the specified event source that has the specified verbosity level or lower, and matching keyword flags.</summary>
         <remarks>
@@ -364,7 +364,7 @@
       </Parameters>
       <Docs>
         <param name="eventSource">The event source to enable events for.</param>
-        <param name="level">The level of events to enable.</param>
+        <param name="level">The level of events to enable. Using EventLevel.LogAlways includes events of all levels.</param>
         <param name="matchAnyKeyword">The keyword flags necessary to enable the events.</param>
         <param name="arguments">The arguments to be matched to enable the events.</param>
         <summary>Enables events for the specified event source that has the specified verbosity level or lower, matching event keyword flag, and matching arguments.</summary>