hiddenapi: Add constants for 'greylist-max-p'

New category of hidden API has been created. Update the script
generate_hiddenapi_lists.py with the new flag name.

Test: m, phone boots
Change-Id: I79e5478678880939e20e500cb8dad9b2a56fc84f

core/java/android/content/pm/ApplicationInfo.java

@@ -1752,7 +1752,7 @@ public class ApplicationInfo extends PackageItemInfo implements Parcelable {
      * is on the package whitelist.
      *
      * @param policy configured policy for this app, or {@link #HIDDEN_API_ENFORCEMENT_DEFAULT}
-     *               if nothing configured.
+     *        if nothing configured.
      * @hide
      */
     public void maybeUpdateHiddenApiEnforcementPolicy(@HiddenApiEnforcementPolicy int policy) {

tools/hiddenapi/generate_hiddenapi_lists.py

@@ -26,6 +26,7 @@ FLAG_WHITELIST = "whitelist"
 FLAG_GREYLIST = "greylist"
 FLAG_BLACKLIST = "blacklist"
 FLAG_GREYLIST_MAX_O = "greylist-max-o"
+FLAG_GREYLIST_MAX_P = "greylist-max-p"
 
 # List of all known flags.
 FLAGS = [
@@ -33,6 +34,7 @@ FLAGS = [
     FLAG_GREYLIST,
     FLAG_BLACKLIST,
     FLAG_GREYLIST_MAX_O,
+    FLAG_GREYLIST_MAX_P,
 ]
 FLAGS_SET = set(FLAGS)