Fixes crash from selecting uninstalled app info from recents.

- when the package is uninstalled, also remove it from the recent tasks
- move retrieveAppEntry() from onCreate() to getPreferenceControllers()
so that if the package info is invalid, do not create any controllers,
as the activity will be finished anyway.

Change-Id: Ibbfa16e3d1f941a0a200e78ec73a06ca8511f82b
Fixes: 72656345
Test: make RunSettingsRoboTests

tests/robotests/src/com/android/settings/applications/appinfo/AppInfoDashboardFragmentTest.java

@@ -19,6 +19,7 @@ package com.android.settings.applications.appinfo;
 import static com.google.common.truth.Truth.assertThat;
 
 import static org.mockito.ArgumentMatchers.nullable;
+import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
@@ -190,6 +191,22 @@ public final class AppInfoDashboardFragmentTest {
         verify(mActivity).invalidateOptionsMenu();
     }
 
+    @Test
+    public void onActivityResult_packageUninstalled_shouldFinishAndRemoveTask() {
+        doReturn(false).when(mFragment).refreshUi();
+
+        mFragment.onActivityResult(mFragment.REQUEST_UNINSTALL, 0, mock(Intent.class));
+
+        verify(mActivity).finishAndRemoveTask();
+    }
+
+    @Test
+    public void getPreferenceControllers_noPackageInfo_shouldReturnNull() {
+        doNothing().when(mFragment).retrieveAppEntry();
+
+        assertThat(mFragment.getPreferenceControllers(mShadowContext)).isNull();
+    }
+
     @Test
     public void getNumberOfUserWithPackageInstalled_twoUsersInstalled_shouldReturnTwo()
             throws PackageManager.NameNotFoundException{