Improve delete fingerprint UI.

- Make fingerprint preference use two_target preference
- And add a delete button as secondary target
- Remove delete fingerint code from RenameDeleteDialog, and move to new
  DeleteFingerprintDialog
- Some code cleanup
- Tests

Change-Id: I49d9c7d1d03497f07c7e20a805f23e6da934f587
Fix: 37783186
Test: make RunSettingsRoboTests

tests/robotests/src/com/android/settings/fingerprint/DeleteFingerprintDialogTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.fingerprint;
+
+
+import android.app.Dialog;
+import android.hardware.fingerprint.Fingerprint;
+
+import com.android.settings.TestConfig;
+import com.android.settings.fingerprint.FingerprintSettings.FingerprintSettingsFragment;
+import com.android.settings.fingerprint.FingerprintSettings.FingerprintSettingsFragment
+        .DeleteFingerprintDialog;
+import com.android.settings.testutils.SettingsRobolectricTestRunner;
+import com.android.settings.testutils.shadow.ShadowEventLogWriter;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.annotation.Config;
+import org.robolectric.util.FragmentTestUtil;
+
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+
+@RunWith(SettingsRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION,
+        shadows = {
+                ShadowEventLogWriter.class
+        })
+public class DeleteFingerprintDialogTest {
+
+    @Mock
+    private FingerprintSettingsFragment mTarget;
+    @Mock
+    private Fingerprint mFingerprint;
+    private DeleteFingerprintDialog mFragment;
+
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mFragment = DeleteFingerprintDialog.newInstance(mFingerprint, mTarget);
+    }
+
+    @Test
+    public void launchDialog_clickPositive_shouldDeleteFingerprint() {
+        FragmentTestUtil.startFragment(mFragment);
+
+        mFragment.onClick(mFragment.getDialog(), Dialog.BUTTON_POSITIVE);
+
+        verify(mTarget).deleteFingerPrint(mFingerprint);
+    }
+
+    @Test
+    public void launchDialog_clickNegative_shouldDoNothing() {
+        FragmentTestUtil.startFragment(mFragment);
+
+        mFragment.onClick(mFragment.getDialog(), Dialog.BUTTON_NEGATIVE);
+
+        verify(mTarget, never()).deleteFingerPrint(mFingerprint);
+    }
+}