Revert of Adding a router class to handle messages that expect responses.

mojo/bindings/java/src/org/chromium/mojo/bindings/Message.java

Index: mojo/bindings/java/src/org/chromium/mojo/bindings/Message.java
diff --git a/mojo/bindings/java/src/org/chromium/mojo/bindings/Message.java b/mojo/bindings/java/src/org/chromium/mojo/bindings/Message.java
index 07bd2bd2e4697516242c73ef017cb10fbe4a198b..ee687070127fff4b5f6b896de6c61c493a6584d4 100644
--- a/mojo/bindings/java/src/org/chromium/mojo/bindings/Message.java
+++ b/mojo/bindings/java/src/org/chromium/mojo/bindings/Message.java
@@ -6,6 +6,8 @@
 
 import org.chromium.mojo.system.Handle;
 import org.chromium.mojo.system.MessagePipeHandle;
+import org.chromium.mojo.system.MessagePipeHandle.ReadMessageResult;
+import org.chromium.mojo.system.MojoResult;
 
 import java.nio.ByteBuffer;
 import java.util.List;
@@ -36,4 +38,26 @@
         this.buffer = buffer;
         this.handles = handles;
     }
+
+    /**
+     * Read a message, and pass it to the given |MessageReceiver| if not null. If the
+     * |MessageReceiver| is null, the message is lost.
+     *
+     * @param receiver The {@link MessageReceiver} that will receive the read {@link Message}. Can
+     *            be <code>null</code>, in which case the message is discarded.
+     */
+    public static int readAndDispatchMessage(MessagePipeHandle handle, MessageReceiver receiver) {
+        // TODO(qsr) Allow usage of a pool of pre-allocated buffer for performance.
+        ReadMessageResult result = handle.readMessage(null, 0, MessagePipeHandle.ReadFlags.NONE);
+        if (result.getMojoResult() != MojoResult.RESOURCE_EXHAUSTED) {
+            return result.getMojoResult();
+        }
+        ByteBuffer buffer = ByteBuffer.allocateDirect(result.getMessageSize());
+        result = handle.readMessage(buffer, result.getHandlesCount(),
+                MessagePipeHandle.ReadFlags.NONE);
+        if (receiver != null && result.getMojoResult() == MojoResult.OK) {
+            receiver.accept(new Message(buffer, result.getHandles()));
+        }
+        return result.getMojoResult();
+    }
 }