Add missing docs to notification style rebuilder functions.

Bug: 6914726
Change-Id: I13efae036610523ec6f83696d3337054e79856aa

Author: cwren

core/java/android/app/Notification.java

@@ -1731,6 +1731,9 @@ public BigPictureStyle setSummaryText(CharSequence cs) {
             return this;
         }
 
+        /**
+         * Provide the bitmap to be used as the payload for the BigPicture notification.
+         */
         public BigPictureStyle bigPicture(Bitmap b) {
             mPicture = b;
             return this;
@@ -1809,6 +1812,10 @@ public BigTextStyle setSummaryText(CharSequence cs) {
             return this;
         }
 
+        /**
+         * Provide the longer text to be displayed in the big form of the
+         * template in place of the content text.
+         */
         public BigTextStyle bigText(CharSequence cs) {
             mBigText = cs;
             return this;
@@ -1889,6 +1896,9 @@ public InboxStyle setSummaryText(CharSequence cs) {
             return this;
         }
 
+        /**
+         * Append a line to the digest section of the Inbox notification.
+         */
         public InboxStyle addLine(CharSequence cs) {
             mTexts.add(cs);
             return this;