Remove fluent-style from newtransport Stream.

The fluent-style wasn't being used, yet made it impossible to
simultaneously implement both ClientStream and ServerStream. Having a
single class that switches between client and server behavior based on a
boolean is helpful to some transports.
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=69028356

core/src/main/java/com/google/net/stubby/newtransport/ClientStream.java

@@ -4,7 +4,7 @@ package com.google.net.stubby.newtransport;
 /**
  * Extension of {@link Stream} to support client-side termination semantics.
  */
-public interface ClientStream extends Stream<ClientStream> {
+public interface ClientStream extends Stream {
 
   /**
    * Used to abnormally terminate the stream. Any internally buffered messages are dropped. After

core/src/main/java/com/google/net/stubby/newtransport/ServerStream.java

@@ -6,7 +6,7 @@ import com.google.net.stubby.Status;
 /**
  * Extension of {@link Stream} to support server-side termination semantics.
  */
-public interface ServerStream extends Stream<ServerStream> {
+public interface ServerStream extends Stream {
 
   /**
    * Closes the local side of this stream. A status code of

core/src/main/java/com/google/net/stubby/newtransport/Stream.java

@@ -7,7 +7,7 @@ import javax.annotation.Nullable;
 /**
  * A single stream of communication between two end-points within a transport.
  */
-public interface Stream<T extends Stream<T>> {
+public interface Stream {
 
   /**
    * Gets the current state of this stream.
@@ -39,7 +39,7 @@ public interface Stream<T extends Stream<T>> {
    * @param accepted an optional callback for when the transport has accepted the write.
    * @return this stream instance.
    */
-  T writeContext(String name, InputStream value, int length, @Nullable Runnable accepted);
+  void writeContext(String name, InputStream value, int length, @Nullable Runnable accepted);
 
   /**
    * Writes a message payload to the remote end-point. The bytes from the stream are immediate read
@@ -58,10 +58,10 @@ public interface Stream<T extends Stream<T>> {
    * @param accepted an optional callback for when the transport has accepted the write.
    * @return this stream instance.
    */
-  T writeMessage(InputStream message, int length, @Nullable Runnable accepted);
+  void writeMessage(InputStream message, int length, @Nullable Runnable accepted);
 
   /**
    * Flushes any internally buffered messages to the remote end-point.
    */
-  T flush();
+  void flush();
 }