cherry-pick from pi-dev docs: Replacing {#link with {@link

Several java files had the typo {#link (for cross-references to other
Javadocs) instead of the proper {@link format. This was confusing the
new doc publish tool (Mivi) since that's the format used for {# Django
comments #}.

Fixed a couple of links that had other errors (which prevented building
once the {# -> {@ was done) and other typos.

Replaced throughout the frameworks/base project; I'll need a separate CL
for the AndroidX fixes.

(Other files were not in the public Javadocs.)

Bug: 111925950
Test: make ds-docs
Change-Id: Ia06e1fffd814671289a1caebd5962aedc18a28d7
Original Change-Id: Ia06e1fffd814671289a1caebd5962aedc18a28d7
Exempt-From-Owner-Approval: Docs-only change

core/java/android/net/NetworkMisc.java

@@ -46,7 +46,7 @@ public class NetworkMisc implements Parcelable {
 
     /**
      * Set if the user desires to use this network even if it is unvalidated. This field has meaning
-     * only if {#link explicitlySelected} is true. If it is, this field must also be set to the
+     * only if {@link explicitlySelected} is true. If it is, this field must also be set to the
      * appropriate value based on previous user choice.
      */
     public boolean acceptUnvalidated;