Fix xref links (#4535)

* xref fixes

Author: gewarren

xml/System.Activities.Statements/Delay.xml

@@ -25,9 +25,7 @@
       <format type="text/markdown"><![CDATA[  
   
 ## Remarks  
- When the activity's timer expires, the <xref:System.Activities.Statements.Delay> activity completes its execution. If a workflow instance persists while a <xref:System.Activities.Statements.Delay> activity has an outstanding timer, then an <xref:System.ServiceModel.Activities.Description.ITimerExpiredNotification> standard endpoint must be configured to receive notification that the timer has expired.  
-  
-   
+ When the activity's timer expires, the <xref:System.Activities.Statements.Delay> activity completes its execution.
   
 ## Examples  
  The following code sample demonstrates creating a <xref:System.Activities.Statements.Delay> activity. This example is from the [Using the Pick Activity](/dotnet/framework/windows-workflow-foundation/samples/using-the-pick-activity) sample.  

xml/System.Activities/BookmarkScopeHandle.xml

@@ -20,7 +20,7 @@
     </Attribute>
   </Attributes>
   <Docs>
-    <summary>A <see cref="T:System.Handle" /> used to manage the lifetime of a <see cref="T:System.Activities.BookmarkScope" />.</summary>
+    <summary>A <see cref="T:System.Activities.Handle" /> used to manage the lifetime of a <see cref="T:System.Activities.BookmarkScope" />.</summary>
     <remarks>To be added.</remarks>
   </Docs>
   <Members>

xml/System.Data.Metadata.Edm/BuiltInTypeKind.xml

@@ -645,7 +645,7 @@
       </ReturnValue>
       <MemberValue>29</MemberValue>
       <Docs>
-        <summary>An enumeration member that indicates the <see cref="T:System.Data.Metadata.Edm.ProviderManifest" /> type.</summary>
+        <summary>An enumeration member that indicates the <see langword="ProviderManifest" /> type.</summary>
       </Docs>
     </Member>
     <Member MemberName="ReferentialConstraint">

xml/System.Device.Location/GeoCoordinate.xml

@@ -28,7 +28,7 @@
         <AssemblyVersion>4.0.0.0</AssemblyVersion>
       </AssemblyInfo>
       <Docs>
-        <summary>Initializes a new instance of <see cref="T:System.Device.Location.GeoCoordinate." /></summary>
+        <summary>Initializes a new instance of <see cref="T:System.Device.Location.GeoCoordinate" />.</summary>
       </Docs>
     </MemberGroup>
     <Member MemberName=".ctor">

xml/System.Net.Http/ReadOnlyMemoryContent.xml

@@ -23,7 +23,7 @@
   </Base>
   <Interfaces />
   <Docs>
-    <summary>Provides HTTP content based on a <see cref="T:System.ReadOnlyMemory&lt;System.Byte&gt;" />.</summary>
+    <summary>Provides HTTP content based on a <see cref="T:System.ReadOnlyMemory`1" />.</summary>
     <remarks>To be added.</remarks>
   </Docs>
   <Members>

xml/System.Net.Security/SslStream.xml

@@ -1350,7 +1350,7 @@
  ]]></format>
         </remarks>
         <exception cref="T:System.ArgumentNullException">
-          Either <see cref="P:System.Net.Security.SslServerAuthenticationOptions.ServerCertificateSelectionCallback" /> or <see cref="P:System.Net.Security.SslServerAuthenticationOptions.ServerCertificate" /> is <see langword="null" /> and <see cref="T:System.Net.Security.LocalCertificateSelectionCallback" /> is not set in the <see cref="M:System.Net.Security.SslStream.#ctor" /> constructor.</exception>
+          Either <see cref="P:System.Net.Security.SslServerAuthenticationOptions.ServerCertificateSelectionCallback" /> or <see cref="P:System.Net.Security.SslServerAuthenticationOptions.ServerCertificate" /> is <see langword="null" /> and <see cref="T:System.Net.Security.LocalCertificateSelectionCallback" /> is not set in the <see langword="SslStream" /> constructor.</exception>
         <exception cref="T:System.ArgumentNullException">
           <paramref name="sslServerAuthenticationOptions" /> is <see langword="null" />.</exception>
         <exception cref="T:System.Security.Authentication.AuthenticationException">The authentication failed and left this object in an unusable state.</exception>

xml/System.Net/WebClient.xml

@@ -1612,18 +1612,18 @@
  For more information about how to handle events, see [Handling and Raising Events](/dotnet/standard/events/).  
 
 > [!NOTE]
-> A passive FTP file transfer will always show a progress percentage of zero, since the server did not send the file size. To show progress, you can change the FTP connection to active by overriding the <xref:System.Net.WebClient.GetWebRequest%2A> virtual method:  
+> A passive FTP file transfer will always show a progress percentage of zero, since the server did not send the file size. To show progress, you can change the FTP connection to active by overriding the <xref:System.Web.Services.Protocols.WebClientProtocol.GetWebRequest(System.Uri)> virtual method:  
 
-```csharp  
-internal class MyWebClient : WebClient
-{  
+```csharp
+internal class MyWebClient : WebClientProtocol
+{
     protected override WebRequest GetWebRequest(Uri address)
-    {  
-        FtpWebRequest req = (FtpWebRequest)base.GetWebRequest(address);  
-        req.UsePassive = false;  
-        return req;  
-    }  
-}  
+    {
+        FtpWebRequest req = (FtpWebRequest)base.GetWebRequest(address);
+        req.UsePassive = false;
+        return req;
+    }
+}
 ```
 
 ## Examples