Add event tracking to the gesture navigation tutorial.

- Added logs for tutorial step shown/completed and for tutorial skip.
- Added shared preference tracking for tutorial steps completed and for tutorial skip.

Bug:
Test: manual
Change-Id: I47dbdb394db80c5687e98fb034a3883b33f6fd3c

quickstep/src/com/android/quickstep/interaction/AssistantGestureTutorialFragment.java

@@ -15,13 +15,21 @@
  */
 package com.android.quickstep.interaction;
 
+import android.content.SharedPreferences;
 import android.view.MotionEvent;
 import android.view.View;
 
+import com.android.launcher3.logging.StatsLogManager;
 import com.android.quickstep.interaction.TutorialController.TutorialType;
 
 /** Shows the Home gesture interactive tutorial. */
 public class AssistantGestureTutorialFragment extends TutorialFragment {
+
+    protected AssistantGestureTutorialFragment(
+            SharedPreferences sharedPrefs, StatsLogManager statsLogManager) {
+        super(sharedPrefs, statsLogManager);
+    }
+
     @Override
     TutorialController createController(TutorialType type) {
         return new AssistantGestureTutorialController(this, type);
@@ -39,4 +47,14 @@ public class AssistantGestureTutorialFragment extends TutorialFragment {
         }
         return super.onTouch(view, motionEvent);
     }
+
+    @Override
+    void logTutorialStepShown() {
+        // No-Op: tutorial step not currently shown to users
+    }
+
+    @Override
+    void logTutorialStepCompleted() {
+        // No-Op: tutorial step not currently shown to users
+    }
 }