[FAB-15579] Fix doc for CommonIterator.next()

This fixes the explanation for CommonIterator.next() to be consistent
with the actual behavior as follows:
  - next() no longer emits an event
  - next() does not reject when there is no more value, but resolves
    with an object { done: true }

FAB-15579 (1 of 2)

Change-Id: I94767af0767ae56d57cdc6b1b825822f8ae337cc
Signed-off-by: Taku Shimosawa <taku.shimosawa@hal.hitachi.com>

Author: shimos

fabric-shim/lib/iterators.js

@@ -72,11 +72,11 @@ class CommonIterator {
     }
 
     /**
-	 * Get the next value and return it through a promise and also emit
-	 * it if event listeners have been registered.
+	 * Get the next value and return it through a promise.
 	 * @async
-	 * @return {promise} a promise that is fulfilled with the next value or
-	 * is rejected otherwise
+	 * @return {promise} a promise that is fulfilled with an object { value: (next value) },
+	 * is fulfilled with an object { done: true } if there is no more value,
+	 * or is rejected if any error occurs.
 	 */
     async next() {
         // check to see if there are some results left in the current result set