Java: Introduce ResultAnd<> and use it.

mojo/public/java/system/src/org/chromium/mojo/system/DataPipe.java

Index: mojo/public/java/system/src/org/chromium/mojo/system/DataPipe.java
diff --git a/mojo/public/java/system/src/org/chromium/mojo/system/DataPipe.java b/mojo/public/java/system/src/org/chromium/mojo/system/DataPipe.java
index a6683fdde7677877bcb1c5b17d9a7b01d630f1c2..4deaf0975d30f600892992252cc50c7e6cd2f00f 100644
--- a/mojo/public/java/system/src/org/chromium/mojo/system/DataPipe.java
+++ b/mojo/public/java/system/src/org/chromium/mojo/system/DataPipe.java
@@ -234,7 +234,7 @@ public interface DataPipe {
          *
          * @return number of written bytes.
          */
-        public int writeData(ByteBuffer elements, WriteFlags flags);
+        public ResultAnd<Integer> writeData(ByteBuffer elements, WriteFlags flags);
 
         /**
          * Begins a two-phase write to the data pipe producer . On success, returns a |ByteBuffer|
@@ -276,7 +276,6 @@ public interface DataPipe {
      * Handle for the consumer part of a data pipe.
      */
     public static interface ConsumerHandle extends Handle {
-
         /**
          * @see org.chromium.mojo.system.Handle#pass()
          */
@@ -302,7 +301,7 @@ public interface DataPipe {
          * If flags has |query| set, it queries the amount of data available, returning the number
          * of bytes available. In this case |allOrNone| is ignored, as are |elements|.
          */
-        public int readData(ByteBuffer elements, ReadFlags flags);
+        public ResultAnd<Integer> readData(ByteBuffer elements, ReadFlags flags);
 
         /**
          * Begins a two-phase read from the data pipe consumer. On success, returns a |ByteBuffer|