Remove divider above device switcher in panel

Remove the divider above the media device switcher Slice per the request.

Do a little refactor in Panel View, to use DividerItemDecoration instead of adding
divider views in layout file as the recycler view items divider.

Since dividers should be shown in most cases, we are setting DividerCondition to
DIVIDER_CONDITION_BOTH and default true to allow divider.  For the slice we don't
need divider (media device switch in this case) we are setting the the target
direction of isDividerAllowed (above in this case) to false.  Since we have
DIVIDER_CONDITION_BOTH, if one of the item view set the divider not allow, the
divider won't be shown.

Test: Visual/Manual inspection
Fixes: 126205139
Change-Id: Ic857705c90819ef9375f877a44bb32987b5d4438

tests/robotests/src/com/android/settings/panel/PanelSlicesAdapterTest.java

@@ -16,13 +16,18 @@
 
 package com.android.settings.panel;
 
+import static com.android.settings.slices.CustomSliceRegistry.MEDIA_OUTPUT_INDICATOR_SLICE_URI;
+
 import static com.google.common.truth.Truth.assertThat;
 
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.spy;
 
+import android.app.settings.SettingsEnums;
 import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
 
@@ -39,6 +44,9 @@ import org.robolectric.RobolectricTestRunner;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.android.controller.ActivityController;
 
+import java.util.Arrays;
+import java.util.List;
+
 @RunWith(RobolectricTestRunner.class)
 public class PanelSlicesAdapterTest {
 
@@ -48,8 +56,6 @@ public class PanelSlicesAdapterTest {
     private FakeFeatureFactory mFakeFeatureFactory;
     private PanelFeatureProvider mPanelFeatureProvider;
 
-    private PanelSlicesAdapter mAdapter;
-
     @Before
     public void setUp() {
         mContext = RuntimeEnvironment.application;
@@ -70,28 +76,83 @@ public class PanelSlicesAdapterTest {
                                 .get()
                                 .getSupportFragmentManager()
                                 .findFragmentById(R.id.main_content));
-
-        mAdapter = new PanelSlicesAdapter(mPanelFragment, mFakePanelContent);
     }
 
     @Test
     public void onCreateViewHolder_returnsSliceRowViewHolder() {
+        final PanelSlicesAdapter adapter =
+                new PanelSlicesAdapter(mPanelFragment, mFakePanelContent);
         final ViewGroup view = new FrameLayout(mContext);
         final PanelSlicesAdapter.SliceRowViewHolder viewHolder =
-                mAdapter.onCreateViewHolder(view, 0);
+                adapter.onCreateViewHolder(view, 0);
 
         assertThat(viewHolder.sliceView).isNotNull();
     }
 
     @Test
     public void onBindViewHolder_bindsSlice() {
+        final PanelSlicesAdapter adapter =
+                new PanelSlicesAdapter(mPanelFragment, mFakePanelContent);
         final int position = 0;
         final ViewGroup view = new FrameLayout(mContext);
         final PanelSlicesAdapter.SliceRowViewHolder viewHolder =
-                mAdapter.onCreateViewHolder(view, 0 /* view type*/);
+                adapter.onCreateViewHolder(view, 0 /* view type*/);
 
-        mAdapter.onBindViewHolder(viewHolder, position);
+        adapter.onBindViewHolder(viewHolder, position);
 
         assertThat(viewHolder.sliceLiveData).isNotNull();
     }
+
+    @Test
+    public void nonMediaOutputIndicatorSlice_shouldAllowDividerAboveAndBelow() {
+        final PanelSlicesAdapter adapter =
+                new PanelSlicesAdapter(mPanelFragment, mFakePanelContent);
+        final int position = 0;
+        final ViewGroup view = new FrameLayout(mContext);
+        final PanelSlicesAdapter.SliceRowViewHolder viewHolder =
+                adapter.onCreateViewHolder(view, 0 /* view type*/);
+
+        adapter.onBindViewHolder(viewHolder, position);
+
+        assertThat(viewHolder.isDividerAllowedAbove()).isTrue();
+        assertThat(viewHolder.isDividerAllowedBelow()).isTrue();
+    }
+
+    @Test
+    public void mediaOutputIndicatorSlice_shouldNotAllowDividerAbove() {
+        PanelContent mediaOutputIndicatorSlicePanelContent = new PanelContent() {
+            @Override
+            public CharSequence getTitle() {
+                return "title";
+            }
+
+            @Override
+            public List<Uri> getSlices() {
+                return Arrays.asList(
+                        MEDIA_OUTPUT_INDICATOR_SLICE_URI
+                );
+            }
+
+            @Override
+            public Intent getSeeMoreIntent() {
+                return new Intent();
+            }
+
+            @Override
+            public int getMetricsCategory() {
+                return SettingsEnums.TESTING;
+            }
+        };
+
+        final PanelSlicesAdapter adapter =
+                new PanelSlicesAdapter(mPanelFragment, mediaOutputIndicatorSlicePanelContent);
+        final int position = 0;
+        final ViewGroup view = new FrameLayout(mContext);
+        final PanelSlicesAdapter.SliceRowViewHolder viewHolder =
+                adapter.onCreateViewHolder(view, 0 /* view type*/);
+
+        adapter.onBindViewHolder(viewHolder, position);
+
+        assertThat(viewHolder.isDividerAllowedAbove()).isFalse();
+    }
 }