8241760: Typos: empty lines in javadoc, inconsistent indents, etc. (net and nio)

Reviewed-by: alanb, prappo, dfuchs

src/java.base/share/classes/java/nio/channels/AsynchronousChannelGroup.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2020, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -332,7 +332,7 @@ public abstract class AsynchronousChannelGroup {
 
     /**
      * Awaits termination of the group.
-
+     *
      * <p> This method blocks until the group has terminated, or the timeout
      * occurs, or the current thread is interrupted, whichever happens first.
      *

src/java.base/share/classes/java/nio/channels/SelectionKey.java

@@ -346,7 +346,7 @@ public abstract class SelectionKey {
      * method always returns {@code false}.  </p>
      *
      * @return  {@code true} if, and only if,
-                {@code readyOps() & OP_READ} is nonzero
+     *          {@code readyOps() & OP_READ} is nonzero
      *
      * @throws  CancelledKeyException
      *          If this key has been cancelled