Add display settings dashboard to new IA.

- Added a activity-alias pointing to displaySettings as top level
  setting item.
- Refactored all preference logic in DisplaySettings into
  PreferenceControllers. During fragment onAttach it installs all
  controllers, and during onResume it updates preference state. Each
  controller listens to its own preference change event.

Bug: 31800242
Test: RunSettingsRoboTests
Change-Id: Ibc9bf200c5acce7c4ae9292340822afee27a3a28

tests/robotests/src/com/android/settings/core/PreferenceControllerTest.java

@@ -29,8 +29,6 @@ import org.mockito.MockitoAnnotations;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
 
-import java.util.List;
-
 import static org.mockito.Matchers.any;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
@@ -39,7 +37,6 @@ import static org.mockito.Mockito.when;
 @RunWith(RobolectricTestRunner.class)
 @Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
 public class PreferenceControllerTest {
-    private static final String KEY_PREF = "test_pref";
 
     @Mock
     private Context mContext;
@@ -58,39 +55,60 @@ public class PreferenceControllerTest {
 
     @Test
     public void removeExistingPref_shouldBeRemoved() {
-        when(mScreen.findPreference(KEY_PREF)).thenReturn(mPreference);
+        when(mScreen.findPreference(TestPrefController.KEY_PREF)).thenReturn(mPreference);
 
-        mTestPrefController.removePreference(mScreen, KEY_PREF);
+        mTestPrefController.removePreference(mScreen, TestPrefController.KEY_PREF);
 
         verify(mScreen).removePreference(mPreference);
     }
 
     @Test
     public void removeNonExistingPref_shouldNotRemoveAnything() {
-        mTestPrefController.removePreference(mScreen, KEY_PREF);
+        mTestPrefController.removePreference(mScreen, TestPrefController.KEY_PREF);
 
         verify(mScreen, never()).removePreference(any(Preference.class));
     }
 
+    @Test
+    public void displayPref_ifAvailable() {
+        mTestPrefController.isAvailable = true;
+
+        mTestPrefController.displayPreference(mScreen);
+
+        verify(mScreen, never()).removePreference(any(Preference.class));
+    }
+
+    @Test
+    public void doNotDisplayPref_ifNotAvailable() {
+        when(mScreen.findPreference(TestPrefController.KEY_PREF)).thenReturn(mPreference);
+        mTestPrefController.isAvailable = false;
+
+        mTestPrefController.displayPreference(mScreen);
+
+        verify(mScreen).removePreference(any(Preference.class));
+    }
+
     private class TestPrefController extends PreferenceController {
+        private static final String KEY_PREF = "test_pref";
+        public boolean isAvailable;
 
         public TestPrefController(Context context) {
             super(context);
         }
 
-        @Override
-        public void displayPreference(PreferenceScreen screen) {
-
-        }
-
         @Override
         public boolean handlePreferenceTreeClick(Preference preference) {
             return false;
         }
 
         @Override
-        public void updateNonIndexableKeys(List<String> keys) {
+        protected boolean isAvailable() {
+            return isAvailable;
+        }
 
+        @Override
+        protected String getPreferenceKey() {
+            return KEY_PREF;
         }
     }
 

tests/robotests/src/com/android/settings/dashboard/DashboardFragmentTest.java

@@ -116,15 +116,20 @@ public class DashboardFragmentTest {
         }
 
         @Override
-        public void displayPreference(PreferenceScreen screen) {
-
+        public boolean handlePreferenceTreeClick(Preference preference) {
+            return false;
         }
 
         @Override
-        public boolean handlePreferenceTreeClick(Preference preference) {
+        protected boolean isAvailable() {
             return false;
         }
 
+        @Override
+        protected String getPreferenceKey() {
+            return null;
+        }
+
         @Override
         public void updateNonIndexableKeys(List<String> keys) {
 
@@ -157,10 +162,6 @@ public class DashboardFragmentTest {
             return CategoryKey.CATEGORY_HOMEPAGE;
         }
 
-        @Override
-        protected void displayResourceTiles() {
-        }
-
         @Override
         public PreferenceScreen getPreferenceScreen() {
             return mScreen;
@@ -170,6 +171,16 @@ public class DashboardFragmentTest {
         protected String getLogTag() {
             return "TEST_FRAG";
         }
+
+        @Override
+        protected int getPreferenceScreenResId() {
+            return 0;
+        }
+
+        @Override
+        protected List<PreferenceController> getPreferenceControllers(Context context) {
+            return null;
+        }
     }
 
 }

tests/robotests/src/com/android/settings/deviceinfo/SystemUpdatePreferenceControllerTest.java

@@ -37,7 +37,6 @@ import java.util.List;
 import static com.google.common.truth.Truth.assertThat;
 import static org.mockito.Answers.RETURNS_DEEP_STUBS;
 import static org.mockito.Matchers.any;
-import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -79,14 +78,14 @@ public class SystemUpdatePreferenceControllerTest {
 
         mController.updateNonIndexableKeys(keys);
 
-        assertThat(keys.size()).isEqualTo(2);
+        assertThat(keys.size()).isEqualTo(1);
     }
 
     @Test
     public void displayPrefs_nothingAvailable_shouldNotDisplay() {
         mController.displayPreference(mScreen);
 
-        verify(mScreen, times(2)).removePreference(any(Preference.class));
+        verify(mScreen).removePreference(any(Preference.class));
     }
 
     @Test