Show an 'Undo' snackbar when users dismiss a predicted hotseat item.

Bug: 200841778
Test: Hard-coded the flag to be true, and verified that the snack bar
is shown with the correct text. Also verified that talkback announces
"Item Removed" properly and that the correct log event is produced by
the AppEventProducer which AiAi needs to process the user action.

Change-Id: Ifbb9cf7aecf26cd4bcebf48d4fb07fb3d5af46bb
diff --git a/quickstep/src/com/android/launcher3/model/AppEventProducer.java b/quickstep/src/com/android/launcher3/model/AppEventProducer.java
index 3f29e43..5c66944 100644
--- a/quickstep/src/com/android/launcher3/model/AppEventProducer.java
+++ b/quickstep/src/com/android/launcher3/model/AppEventProducer.java
@@ -18,6 +18,7 @@
 import static android.app.prediction.AppTargetEvent.ACTION_DISMISS;
 import static android.app.prediction.AppTargetEvent.ACTION_LAUNCH;
 import static android.app.prediction.AppTargetEvent.ACTION_PIN;
+import static android.app.prediction.AppTargetEvent.ACTION_UNDISMISS;
 import static android.app.prediction.AppTargetEvent.ACTION_UNPIN;
 
 import static com.android.launcher3.LauncherSettings.Favorites.CONTAINER_HOTSEAT_PREDICTION;
@@ -25,6 +26,7 @@
 import static com.android.launcher3.LauncherSettings.Favorites.CONTAINER_WIDGETS_PREDICTION;
 import static com.android.launcher3.logger.LauncherAtomExtensions.ExtendedContainers.ContainerCase.DEVICE_SEARCH_RESULT_CONTAINER;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_APP_LAUNCH_TAP;
+import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_DISMISS_PREDICTION_UNDO;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_FOLDER_CONVERTED_TO_ICON;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_HOTSEAT_PREDICTION_PINNED;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_ITEM_DRAG_STARTED;
@@ -176,6 +178,8 @@
                     mContext.getPackageName(), Process.myUserHandle())
                     .build();
             sendEvent(target, atomInfo, ACTION_LAUNCH, CONTAINER_PREDICTION);
+        } else if (event == LAUNCHER_DISMISS_PREDICTION_UNDO) {
+            sendEvent(atomInfo, ACTION_UNDISMISS, CONTAINER_HOTSEAT_PREDICTION);
         }
     }
 
diff --git a/src/com/android/launcher3/SecondaryDropTarget.java b/src/com/android/launcher3/SecondaryDropTarget.java
index cd06414..5b037e4 100644
--- a/src/com/android/launcher3/SecondaryDropTarget.java
+++ b/src/com/android/launcher3/SecondaryDropTarget.java
@@ -8,6 +8,7 @@
 import static com.android.launcher3.accessibility.LauncherAccessibilityDelegate.DISMISS_PREDICTION;
 import static com.android.launcher3.accessibility.LauncherAccessibilityDelegate.RECONFIGURE;
 import static com.android.launcher3.accessibility.LauncherAccessibilityDelegate.UNINSTALL;
+import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_DISMISS_PREDICTION_UNDO;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_ITEM_DROPPED_ON_DONT_SUGGEST;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_ITEM_DROPPED_ON_UNINSTALL;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_ITEM_UNINSTALL_CANCELLED;
@@ -46,6 +47,7 @@
 import com.android.launcher3.model.data.LauncherAppWidgetInfo;
 import com.android.launcher3.util.PackageManagerHelper;
 import com.android.launcher3.util.PendingRequestArgs;
+import com.android.launcher3.views.Snackbar;
 import com.android.launcher3.widget.LauncherAppWidgetProviderInfo;
 
 import java.net.URISyntaxException;
@@ -220,7 +222,8 @@
 
     @Override
     public void completeDrop(final DragObject d) {
-        ComponentName target = performDropAction(getViewUnderDrag(d.dragInfo), d.dragInfo);
+        ComponentName target = performDropAction(getViewUnderDrag(d.dragInfo), d.dragInfo,
+                d.logInstanceId);
         if (d.dragSource instanceof DeferredOnComplete) {
             DeferredOnComplete deferred = (DeferredOnComplete) d.dragSource;
             if (target != null) {
@@ -264,7 +267,7 @@
      * Performs the drop action and returns the target component for the dragObject or null if
      * the action was not performed.
      */
-    protected ComponentName performDropAction(View view, ItemInfo info) {
+    protected ComponentName performDropAction(View view, ItemInfo info, InstanceId instanceId) {
         if (mCurrentAccessibilityAction == RECONFIGURE) {
             int widgetId = getReconfigurableWidgetId(view);
             if (widgetId != INVALID_APPWIDGET_ID) {
@@ -276,7 +279,16 @@
             return null;
         }
         if (mCurrentAccessibilityAction == DISMISS_PREDICTION) {
-            // We sent the log event, nothing else left to do
+            if (FeatureFlags.ENABLE_DISMISS_PREDICTION_UNDO.get()) {
+                mLauncher.getDragLayer()
+                        .announceForAccessibility(getContext().getString(R.string.item_removed));
+                Snackbar.show(mLauncher, R.string.item_removed, R.string.undo, () -> { }, () -> {
+                    mStatsLogManager.logger()
+                            .withInstanceId(instanceId)
+                            .withItemInfo(info)
+                            .log(LAUNCHER_DISMISS_PREDICTION_UNDO);
+                });
+            }
             return null;
         }
         // else: mCurrentAccessibilityAction == UNINSTALL
@@ -303,8 +315,9 @@
 
     @Override
     public void onAccessibilityDrop(View view, ItemInfo item) {
-        doLog(new InstanceIdSequence().newInstanceId(), item);
-        performDropAction(view, item);
+        InstanceId instanceId = new InstanceIdSequence().newInstanceId();
+        doLog(instanceId, item);
+        performDropAction(view, item, instanceId);
     }
 
     /**
diff --git a/src/com/android/launcher3/config/FeatureFlags.java b/src/com/android/launcher3/config/FeatureFlags.java
index 420180b..626e15c 100644
--- a/src/com/android/launcher3/config/FeatureFlags.java
+++ b/src/com/android/launcher3/config/FeatureFlags.java
@@ -265,6 +265,10 @@
             "USE_LOCAL_ICON_OVERRIDES", true,
             "Use inbuilt monochrome icons if app doesn't provide one");
 
+    public static final BooleanFlag ENABLE_DISMISS_PREDICTION_UNDO = getDebugFlag(
+            "ENABLE_DISMISS_PREDICTION_UNDO", false,
+            "Show an 'Undo' snackbar when users dismiss a predicted hotseat item");
+
     public static void initialize(Context context) {
         synchronized (sDebugFlags) {
             for (DebugFlag flag : sDebugFlags) {
diff --git a/src/com/android/launcher3/logging/StatsLogManager.java b/src/com/android/launcher3/logging/StatsLogManager.java
index b8ecec1..7e6f81c 100644
--- a/src/com/android/launcher3/logging/StatsLogManager.java
+++ b/src/com/android/launcher3/logging/StatsLogManager.java
@@ -579,7 +579,10 @@
         LAUNCHER_TASKBAR_OVERVIEW_BUTTON_LONGPRESS(1010),
 
         @UiEvent(doc = "User tapped taskbar a11y button")
-        LAUNCHER_TASKBAR_A11Y_BUTTON_LONGPRESS(1011);
+        LAUNCHER_TASKBAR_A11Y_BUTTON_LONGPRESS(1011),
+
+        @UiEvent(doc = "Show an 'Undo' snackbar when users dismiss a predicted hotseat item")
+        LAUNCHER_DISMISS_PREDICTION_UNDO(1035);
 
         // ADD MORE