Use Quickstep ActivityOptions when launching activities from App Widgets

Set a Quickstep specific InteractionHandler on QuickstepLauncher's
AppWidgetHost, which provides QuickstepTransitionManager-generated
ActivityOptions when starting activities from app widget interactions.

Bug: 169042867
Test: manual
Topic: quickstep-widget-app-launch
Change-Id: I231122b09aede940c047f19a5b5d1e7c562f6d3f
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index 5091543..3236f5d 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -436,8 +436,7 @@
         mOnboardingPrefs = createOnboardingPrefs(mSharedPrefs);
 
         mAppWidgetManager = new WidgetManagerHelper(this);
-        mAppWidgetHost = new LauncherAppWidgetHost(this,
-                appWidgetId -> getWorkspace().removeWidget(appWidgetId));
+        mAppWidgetHost = createAppWidgetHost();
         mAppWidgetHost.startListening();
 
         inflateRootView(R.layout.launcher);
@@ -1428,6 +1427,11 @@
         return mAppWidgetHost;
     }
 
+    protected LauncherAppWidgetHost createAppWidgetHost() {
+        return new LauncherAppWidgetHost(this,
+                appWidgetId -> getWorkspace().removeWidget(appWidgetId));
+    }
+
     public LauncherModel getModel() {
         return mModel;
     }