Remove unnecessary method.

Author: arturobernalg

httpclient5/src/main/java/org/apache/hc/client5/http/impl/ProtocolSwitchStrategy.java

@@ -106,24 +106,6 @@ private boolean containsConnectionUpgrade(final HttpMessage message) {
         return found.get();
     }
 
-    private boolean containsUpgradeToken(final CharSequence buffer, final ParserCursor cursor) throws ProtocolException {
-        while (!cursor.atEnd()) {
-            TOKENIZER.skipWhiteSpace(buffer, cursor);
-            final String token = TOKENIZER.parseToken(buffer, cursor, UPGRADE_TOKEN_DELIMITER);
-            if (token.equalsIgnoreCase("upgrade")) {
-                return true;
-            }
-            TOKENIZER.skipWhiteSpace(buffer, cursor);
-            if (!cursor.atEnd()) {
-                final char ch = buffer.charAt(cursor.getPos());
-                if (ch == ',') {
-                    cursor.updatePos(cursor.getPos() + 1);
-                }
-            }
-        }
-        return false;
-    }
-
     private ProtocolVersion parseProtocolVersion(final CharSequence buffer, final ParserCursor cursor) throws ProtocolException {
         TOKENIZER.skipWhiteSpace(buffer, cursor);
         final String proto = TOKENIZER.parseToken(buffer, cursor, LAX_PROTO_DELIMITER);