change MergeFrom_Internal to InternalMergeFrom

diff --git a/csharp/src/Google.Protobuf/Collections/MapField.cs b/csharp/src/Google.Protobuf/Collections/MapField.cs
index 8a6a219..9ed86e8 100644
--- a/csharp/src/Google.Protobuf/Collections/MapField.cs
+++ b/csharp/src/Google.Protobuf/Collections/MapField.cs

@@ -692,7 +692,7 @@
                 }

 

                 [SecuritySafeCritical]

-                public void MergeFrom_Internal(ref ParseContext ctx)

+                public void InternalMergeFrom(ref ParseContext ctx)

                 {

                     // TODO(jtattermusch): deduplicate code

                     uint tag;


diff --git a/csharp/src/Google.Protobuf/IBufferMessage.cs b/csharp/src/Google.Protobuf/IBufferMessage.cs
index 5fccc87..f6d174b 100644
--- a/csharp/src/Google.Protobuf/IBufferMessage.cs
+++ b/csharp/src/Google.Protobuf/IBufferMessage.cs

@@ -43,7 +43,7 @@
         /// Internal implementation of merging data from given parse context into this message.
         /// Users should never invoke this method directly.
         /// </summary>        
-        void MergeFrom_Internal(ref ParseContext ctx);
+        void InternalMergeFrom(ref ParseContext ctx);
     }
 #endif
 }

diff --git a/csharp/src/Google.Protobuf/ParsingPrimitivesMessages.cs b/csharp/src/Google.Protobuf/ParsingPrimitivesMessages.cs
index 12388d1..472fc2f 100644
--- a/csharp/src/Google.Protobuf/ParsingPrimitivesMessages.cs
+++ b/csharp/src/Google.Protobuf/ParsingPrimitivesMessages.cs

@@ -168,19 +168,19 @@
         {
             if (message is IBufferMessage bufferMessage)
             {
-                bufferMessage.MergeFrom_Internal(ref ctx);   
+                bufferMessage.InternalMergeFrom(ref ctx);   
             }
             else
             {
                 // If we reached here, it means we've ran into a nested message with older generated code
-                // which doesn't provide the MergeFrom_Internal method that takes a ParseContext.
+                // which doesn't provide the InternalMergeFrom method that takes a ParseContext.
                 // With a slight performance overhead, we can still parse this message just fine,
                 // but we need to find the original CodedInputStream instance that initiated this
                 // parsing process and make sure its internal state is up to date.
                 // Note that this performance overhead is not very high (basically copying contents of a struct)
                 // and it will only be incurred in case the application mixes older and newer generated code.
                 // Regenerating the code from .proto files will remove this overhead because it will
-                // generate the MergeFrom_Internal method we need.
+                // generate the InternalMergeFrom method we need.
 
                 if (ctx.state.codedInputStream == null)
                 {