Using package update event as well for restoring promise icons

> Sometimes a system app can be in disabled state. When the app is
enabled or disabled, the system sends onPackageChanged event instead
of onPackageAdded/onPackagesRemoved.

Bug: 36911898
Change-Id: Id82f70421b95b23f9891c8d4b0b7e0e1d4cddf7b
diff --git a/src/com/android/launcher3/model/PackageUpdatedTask.java b/src/com/android/launcher3/model/PackageUpdatedTask.java
index 9a91583..b58efb6 100644
--- a/src/com/android/launcher3/model/PackageUpdatedTask.java
+++ b/src/com/android/launcher3/model/PackageUpdatedTask.java
@@ -226,7 +226,9 @@
                         if (cn != null && matcher.matches(si, cn)) {
                             AppInfo appInfo = addedOrUpdatedApps.get(cn);
 
-                            if (si.isPromise() && mOp == OP_ADD) {
+                            // For system apps, package manager send OP_UPDATE when an
+                            // app is enabled.
+                            if (si.isPromise() && (mOp == OP_ADD || mOp == OP_UPDATE)) {
                                 if (si.hasStatusFlag(ShortcutInfo.FLAG_AUTOINSTALL_ICON)) {
                                     // Auto install icon
                                     LauncherAppsCompat launcherApps