Fix ensureCapacity in org.h2.mvstore.WriteBuffer.put(ByteBuffer)

h2/src/main/org/h2/mvstore/WriteBuffer.java

@@ -185,7 +185,7 @@ public class WriteBuffer {
      * @return this
      */
     public WriteBuffer put(ByteBuffer src) {
-        ensureCapacity(buff.remaining()).put(src);
+        ensureCapacity(src.remaining()).put(src);
         return this;
     }