Show a link to app settings in notification guts.

Test: runtest systemui, cts
Change-Id: I7204102d5c83d589af5d3da57f72068491c12daa
diff --git a/core/java/android/app/Notification.java b/core/java/android/app/Notification.java
index 161dd25..6d7486b 100644
--- a/core/java/android/app/Notification.java
+++ b/core/java/android/app/Notification.java
@@ -103,8 +103,7 @@
 
     /**
      * An activity that provides a user interface for adjusting notification preferences for its
-     * containing application. Optional but recommended for apps that post
-     * {@link android.app.Notification Notifications}.
+     * containing application.
      */
     @SdkConstant(SdkConstantType.INTENT_CATEGORY)
     public static final String INTENT_CATEGORY_NOTIFICATION_PREFERENCES
@@ -113,11 +112,25 @@
     /**
      * Optional extra for {@link #INTENT_CATEGORY_NOTIFICATION_PREFERENCES}. If provided, will
      * contain a {@link NotificationChannel#getId() channel id} that can be used to narrow down
-     * what in app notifications settings should be shown.
+     * what settings should be shown in the target app.
      */
     public static final String EXTRA_CHANNEL_ID = "android.intent.extra.CHANNEL_ID";
 
     /**
+     * Optional extra for {@link #INTENT_CATEGORY_NOTIFICATION_PREFERENCES}. If provided, will
+     * contain the tag provided to {@link NotificationManager#notify(String, int, Notification)}
+     * that can be used to narrow down what settings should be shown in the target app.
+     */
+    public static final String EXTRA_NOTIFICATION_TAG = "android.intent.extra.NOTIFICATION_TAG";
+
+    /**
+     * Optional extra for {@link #INTENT_CATEGORY_NOTIFICATION_PREFERENCES}. If provided, will
+     * contain the id provided to {@link NotificationManager#notify(String, int, Notification)}
+     * that can be used to narrow down what settings should be shown in the target app.
+     */
+    public static final String EXTRA_NOTIFICATION_ID = "android.intent.extra.NOTIFICATION_ID";
+
+    /**
      * Use all default values (where applicable).
      */
     public static final int DEFAULT_ALL = ~0;
@@ -1082,6 +1095,7 @@
     private long mTimeout;
 
     private String mShortcutId;
+    private CharSequence mSettingsText;
 
     /**
      * If this notification is being shown as a badge, always show as a number.
@@ -1851,6 +1865,10 @@
         }
 
         mBadgeIcon = parcel.readInt();
+
+        if (parcel.readInt() != 0) {
+            mSettingsText = TextUtils.CHAR_SEQUENCE_CREATOR.createFromParcel(parcel);
+        }
     }
 
     @Override
@@ -1960,6 +1978,9 @@
 
         that.mChannelId = this.mChannelId;
         that.mTimeout = this.mTimeout;
+        that.mShortcutId = this.mShortcutId;
+        that.mBadgeIcon = this.mBadgeIcon;
+        that.mSettingsText = this.mSettingsText;
 
         if (!heavy) {
             that.lightenPayload(); // will clean out extras
@@ -2229,6 +2250,13 @@
         }
 
         parcel.writeInt(mBadgeIcon);
+
+        if (mSettingsText != null) {
+            parcel.writeInt(1);
+            TextUtils.writeToParcel(mSettingsText, parcel, flags);
+        } else {
+            parcel.writeInt(0);
+        }
     }
 
     /**
@@ -2458,6 +2486,14 @@
         return mShortcutId;
     }
 
+
+    /**
+     * Returns the settings text provided to {@link Builder#setSettingsText(CharSequence)}.
+     */
+    public CharSequence getSettingsText() {
+        return mSettingsText;
+    }
+
     /**
      * The small icon representing this notification in the status bar and content view.
      *
@@ -2887,6 +2923,24 @@
         }
 
         /**
+         * Provides text that will appear as a link to your application's settings.
+         *
+         * <p>This text does not appear within notification {@link Style templates} but may
+         * appear when the user uses an affordance to learn more about the notification.
+         * Additionally, this text will not appear unless you provide a valid link target by
+         * handling {@link #INTENT_CATEGORY_NOTIFICATION_PREFERENCES}.
+         *
+         * <p>This text is meant to be concise description about what the user can customize
+         * when they click on this link. The recommended maximum length is 40 characters.
+         * @param text
+         * @return
+         */
+        public Builder setSettingsText(CharSequence text) {
+            mN.mSettingsText = safeCharSequence(text);
+            return this;
+        }
+
+        /**
          * Set the remote input history.
          *
          * This should be set to the most recent inputs that have been sent