Fix some unused imports and warnings

src/main/java/org/jboss/netty/channel/ChannelLocal.java

@@ -71,7 +71,7 @@ public class ChannelLocal<T> {
      * Returns the initial value of the variable.  By default, it returns
      * {@code null}.  Override it to change the initial value.
      */
-    protected T initialValue(@SuppressWarnings("unused") Channel channel) {
+    protected T initialValue(Channel channel) {
         return null;
     }
 

src/main/java/org/jboss/netty/channel/socket/nio/NioSocketChannel.java

@@ -29,7 +29,6 @@ import org.jboss.netty.channel.AbstractChannel;
 import org.jboss.netty.channel.Channel;
 import org.jboss.netty.channel.ChannelFactory;
 import org.jboss.netty.channel.ChannelFuture;
-import org.jboss.netty.channel.ChannelFutureListener;
 import org.jboss.netty.channel.ChannelPipeline;
 import org.jboss.netty.channel.ChannelSink;
 import org.jboss.netty.channel.MessageEvent;

src/main/java/org/jboss/netty/handler/codec/http/HttpContentCompressor.java

@@ -20,8 +20,6 @@ import org.jboss.netty.handler.codec.compression.ZlibEncoder;
 import org.jboss.netty.handler.codec.compression.ZlibWrapper;
 import org.jboss.netty.handler.codec.embedder.EncoderEmbedder;
 
-import com.sun.net.httpserver.Headers;
-
 /**
  * Compresses an {@link HttpMessage} and an {@link HttpChunk} in {@code gzip} or
  * {@code deflate} encoding while respecting the {@code "Accept-Encoding"} header.

src/main/java/org/jboss/netty/handler/timeout/WriteTimeoutHandler.java

@@ -136,7 +136,7 @@ public class WriteTimeoutHandler extends SimpleChannelDownstreamHandler
         timer.stop();
     }
 
-    protected long getTimeoutMillis(@SuppressWarnings("unused") MessageEvent e) {
+    protected long getTimeoutMillis(MessageEvent e) {
         return timeoutMillis;
     }