Fix kotlin nullable errors in Launcher3

Fix kotlin nullable errors that were exposed by setting the retention
of android.annotation.NonNull and android.annotation.Nullable to
class retention.

Bug: 294110802
Test: builds
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:2608381792389b60ba37c08afcea09dca3c6ff9c)
Merged-In: I26edfec35dca14abe90b08e3c74de0446eda95d2
Change-Id: I26edfec35dca14abe90b08e3c74de0446eda95d2

quickstep/src/com/android/launcher3/taskbar/TaskbarDividerPopupView.kt

@@ -101,10 +101,10 @@ constructor(
     @SuppressLint("UseSwitchCompatOrMaterialCode")
     override fun onFinishInflate() {
         super.onFinishInflate()
-        val taskbarSwitchOption = findViewById<LinearLayout>(R.id.taskbar_switch_option)
-        val alwaysShowTaskbarSwitch = findViewById<Switch>(R.id.taskbar_pinning_switch)
+        val taskbarSwitchOption = requireViewById<LinearLayout>(R.id.taskbar_switch_option)
+        val alwaysShowTaskbarSwitch = requireViewById<Switch>(R.id.taskbar_pinning_switch)
         val navigationModeChangeOption =
-            findViewById<LinearLayout>(R.id.navigation_mode_switch_option)
+            requireViewById<LinearLayout>(R.id.navigation_mode_switch_option)
         alwaysShowTaskbarSwitch.isChecked = alwaysShowTaskbarOn
         taskbarSwitchOption.setOnClickListener {
             alwaysShowTaskbarSwitch.isClickable = true

quickstep/src/com/android/quickstep/util/SplitSelectDataHolder.kt

@@ -156,18 +156,19 @@ class SplitSelectDataHolder(
      */
     fun setSecondTask(pendingIntent: PendingIntent) {
         secondPendingIntent = pendingIntent
-        secondUser = pendingIntent.creatorUserHandle!!
+        secondUser = pendingIntent.creatorUserHandle
     }
 
-    private fun getShortcutInfo(intent: Intent?, user: UserHandle?): ShortcutInfo? {
-        if (intent?.getPackage() == null) {
+    private fun getShortcutInfo(intent: Intent?, user: UserHandle): ShortcutInfo? {
+        val intentPackage = intent?.getPackage()
+        if (intentPackage == null) {
             return null
         }
         val shortcutId = intent.getStringExtra(ShortcutKey.EXTRA_SHORTCUT_ID)
                 ?: return null
         try {
             val context: Context = context.createPackageContextAsUser(
-                    intent.getPackage(), 0 /* flags */, user)
+                    intentPackage, 0 /* flags */, user)
             return ShortcutInfo.Builder(context, shortcutId).build()
         } catch (e: PackageManager.NameNotFoundException) {
             Log.w(TAG, "Failed to create a ShortcutInfo for " + intent.getPackage())
@@ -250,7 +251,7 @@ class SplitSelectDataHolder(
      * convert [secondIntent]
      */
     private fun convertIntentsToFinalTypes() {
-        initialShortcut = getShortcutInfo(initialIntent, initialUser)
+        initialShortcut = getShortcutInfo(initialIntent, checkNotNull(initialUser))
         initialPendingIntent = getPendingIntent(initialIntent, initialUser)
         initialIntent = null
 
@@ -264,7 +265,7 @@ class SplitSelectDataHolder(
             return
         }
 
-        secondShortcut = getShortcutInfo(secondIntent, secondUser)
+        secondShortcut = getShortcutInfo(secondIntent, checkNotNull(secondUser))
         secondPendingIntent = getPendingIntent(secondIntent, secondUser)
         secondIntent = null
     }
@@ -405,4 +406,4 @@ class SplitSelectDataHolder(
         writer.println("$prefix\tinitialShortcut= $initialShortcut")
         writer.println("$prefix\tsecondShortcut= $secondShortcut")
     }
-}
+}