Add autofill feature API

We now have a software feature for autofill which can be used
by partners to disable it on low-end devices or form factors
for which autofill doesn't make sense.

bug:35956220

Test: manual (requires a custom build)

Change-Id: I6c06462ed9ca3ae93331700dce38a8c08dfd0722
diff --git a/services/java/com/android/server/SystemServer.java b/services/java/com/android/server/SystemServer.java
index f74512a..3b5f9bd 100644
--- a/services/java/com/android/server/SystemServer.java
+++ b/services/java/com/android/server/SystemServer.java
@@ -1540,9 +1540,11 @@
         mSystemServiceManager.startService(RetailDemoModeService.class);
         traceEnd();
 
-        traceBeginAndSlog("StartAutoFillService");
-        mSystemServiceManager.startService(AUTO_FILL_MANAGER_SERVICE_CLASS);
-        traceEnd();
+        if (mPackageManager.hasSystemFeature(PackageManager.FEATURE_AUTOFILL)) {
+            traceBeginAndSlog("StartAutoFillService");
+            mSystemServiceManager.startService(AUTO_FILL_MANAGER_SERVICE_CLASS);
+            traceEnd();
+        }
 
         // It is now time to start up the app processes...