diff --git a/car-media-common/src/com/android/car/media/common/MediaItemMetadata.java b/car-media-common/src/com/android/car/media/common/MediaItemMetadata.java
index 5ca60d1..00a4416 100644
--- a/car-media-common/src/com/android/car/media/common/MediaItemMetadata.java
+++ b/car-media-common/src/com/android/car/media/common/MediaItemMetadata.java
@@ -236,6 +236,13 @@
     }
 
     /**
+     * @return optional extras that can include extra information about the media item to be played.
+     */
+    public Bundle getExtras() {
+        return mMediaDescription.getExtras();
+    }
+
+    /**
      * @return boolean that indicate if media is explicit.
      */
     public boolean isExplicit() {
diff --git a/car-media-common/src/com/android/car/media/common/playback/PlaybackViewModel.java b/car-media-common/src/com/android/car/media/common/playback/PlaybackViewModel.java
index e085c00..e4ed555 100644
--- a/car-media-common/src/com/android/car/media/common/playback/PlaybackViewModel.java
+++ b/car-media-common/src/com/android/car/media/common/playback/PlaybackViewModel.java
@@ -598,12 +598,12 @@
         }
 
         /**
-         * Starts playing a given media item. This id corresponds to {@link
-         * MediaItemMetadata#getId()}.
+         * Starts playing a given media item.
          */
-        public void playItem(String mediaItemId) {
+        public void playItem(MediaItemMetadata item) {
             if (mMediaController != null) {
-                mMediaController.getTransportControls().playFromMediaId(mediaItemId, null);
+                mMediaController.getTransportControls().playFromMediaId(item.getId(),
+                        item.getExtras());
             }
         }
 
diff --git a/car-ui-lib/generate_rros.mk b/car-ui-lib/generate_rros.mk
index 4e7931a..7e93c36 100644
--- a/car-ui-lib/generate_rros.mk
+++ b/car-ui-lib/generate_rros.mk
@@ -14,7 +14,7 @@
 # limitations under the License.
 #
 
-# Generates one RRO for a given package
+# Generates one RRO for a given package.
 # $(1) target package name
 # $(2) name of the RRO set (e.g. "base")
 # $(3) resources folder
@@ -23,8 +23,8 @@
 
   rro_package_name := $(2)-$(subst .,-,$(1))
   LOCAL_RESOURCE_DIR := $(3)
+  LOCAL_RRO_THEME := $$(rro_package_name)
   LOCAL_PACKAGE_NAME := $$(rro_package_name)
-  LOCAL_PRODUCT_MODULE := true
   LOCAL_CERTIFICATE := platform
   LOCAL_SDK_VERSION := current
 
diff --git a/car-ui-lib/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBar.java b/car-ui-lib/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBar.java
index c98d114..3dbb6aa 100644
--- a/car-ui-lib/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBar.java
+++ b/car-ui-lib/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBar.java
@@ -29,6 +29,7 @@
 import android.widget.ImageView;
 
 import androidx.annotation.IntRange;
+import androidx.annotation.VisibleForTesting;
 import androidx.recyclerview.widget.OrientationHelper;
 import androidx.recyclerview.widget.RecyclerView;
 
@@ -43,16 +44,19 @@
  * been ported from the PLV with minor updates.
  */
 class DefaultScrollBar implements ScrollBar {
+
+    @VisibleForTesting
+    int mPaddingStart;
+    @VisibleForTesting
+    int mPaddingEnd;
+
     private float mButtonDisabledAlpha;
-    private static final String TAG = "DefaultScrollBar";
     private PagedSnapHelper mSnapHelper;
 
     private ImageView mUpButton;
     private View mScrollView;
     private View mScrollThumb;
     private ImageView mDownButton;
-    private int mPaddingStart;
-    private int mPaddingEnd;
 
     private int mSeparatingMargin;
 
@@ -75,7 +79,7 @@
             @ScrollBarPosition int scrollBarPosition,
             boolean scrollBarAboveRecyclerView) {
 
-        this.mRecyclerView = rv;
+        mRecyclerView = rv;
 
         LayoutInflater inflater =
                 (LayoutInflater) rv.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
@@ -84,7 +88,7 @@
 
         mScrollView = inflater.inflate(R.layout.car_ui_pagedrecyclerview_scrollbar, parent, false);
         mScrollView.setLayoutParams(
-                new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT));
+                new FrameLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT));
 
         Resources res = rv.getContext().getResources();
 
diff --git a/car-ui-lib/tests/robotests/Android.mk b/car-ui-lib/tests/robotests/Android.mk
index 703a6eb..053e733 100644
--- a/car-ui-lib/tests/robotests/Android.mk
+++ b/car-ui-lib/tests/robotests/Android.mk
@@ -39,6 +39,7 @@
     robolectric_android-all-stub \
     Robolectric_all-target \
     mockito-robolectric-prebuilt \
+    testng \
     truth-prebuilt
 
 
@@ -61,6 +62,7 @@
     robolectric_android-all-stub \
     Robolectric_all-target \
     mockito-robolectric-prebuilt \
+    testng \
     truth-prebuilt
 
 LOCAL_TEST_PACKAGE := CarUi
diff --git a/car-ui-lib/tests/robotests/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBarTest.java b/car-ui-lib/tests/robotests/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBarTest.java
new file mode 100644
index 0000000..f0ca4a6
--- /dev/null
+++ b/car-ui-lib/tests/robotests/src/com/android/car/ui/pagedrecyclerview/DefaultScrollBarTest.java
@@ -0,0 +1,130 @@
+/*
+ * Copyright 2019 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.car.ui.pagedrecyclerview;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.testng.Assert.assertThrows;
+
+import android.content.Context;
+import android.widget.FrameLayout;
+
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.android.car.ui.CarUiRobolectricTestRunner;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RuntimeEnvironment;
+import org.robolectric.annotation.Config;
+
+@RunWith(CarUiRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class DefaultScrollBarTest {
+
+    private Context mContext;
+    private ScrollBar mScrollBar;
+
+    @Mock
+    private RecyclerView mRecyclerView;
+    @Mock
+    private FrameLayout mParent;
+    @Mock
+    private FrameLayout.LayoutParams mLayoutParams;
+    @Mock
+    private RecyclerView.RecycledViewPool mRecycledViewPool;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = RuntimeEnvironment.application;
+
+        mScrollBar = new DefaultScrollBar();
+    }
+
+    @Test
+    public void initialize_shouldInitializeScrollListener() {
+        when(mRecyclerView.getContext()).thenReturn(mContext);
+        when(mRecyclerView.getParent()).thenReturn(mParent);
+        when(mRecyclerView.getRecycledViewPool()).thenReturn(mRecycledViewPool);
+        when(mParent.generateLayoutParams(any())).thenReturn(mLayoutParams);
+
+        mScrollBar.initialize(mRecyclerView, 10, PagedRecyclerView.ScrollBarPosition.START, true);
+
+        // called once in DefaultScrollBar and once in SnapHelper while setting up the call backs
+        // when we use attachToRecyclerView(recyclerview)
+        verify(mRecyclerView, times(2)).addOnScrollListener(
+                any(RecyclerView.OnScrollListener.class));
+    }
+
+    @Test
+    public void initialize_shouldSetMaxRecyclerViews() {
+        when(mRecyclerView.getContext()).thenReturn(mContext);
+        when(mRecyclerView.getParent()).thenReturn(mParent);
+        when(mRecyclerView.getRecycledViewPool()).thenReturn(mRecycledViewPool);
+        when(mParent.generateLayoutParams(any())).thenReturn(mLayoutParams);
+
+        mScrollBar.initialize(mRecyclerView, 10, PagedRecyclerView.ScrollBarPosition.START, true);
+
+        verify(mRecycledViewPool).setMaxRecycledViews(0, 12);
+    }
+
+    @Test
+    public void initialize_shouldNotHaveFlingListener() {
+        when(mRecyclerView.getContext()).thenReturn(mContext);
+        when(mRecyclerView.getParent()).thenReturn(mParent);
+        when(mRecyclerView.getRecycledViewPool()).thenReturn(mRecycledViewPool);
+        when(mParent.generateLayoutParams(any())).thenReturn(mLayoutParams);
+
+        mScrollBar.initialize(mRecyclerView, 10, PagedRecyclerView.ScrollBarPosition.START, true);
+
+        verify(mRecyclerView).setOnFlingListener(null);
+    }
+
+    @Test
+    public void setPadding_shouldSetStartAndEndPadding() {
+        when(mRecyclerView.getContext()).thenReturn(mContext);
+        when(mRecyclerView.getParent()).thenReturn(mParent);
+        when(mRecyclerView.getRecycledViewPool()).thenReturn(mRecycledViewPool);
+        when(mParent.generateLayoutParams(any())).thenReturn(mLayoutParams);
+
+        mScrollBar.initialize(mRecyclerView, 10, PagedRecyclerView.ScrollBarPosition.START, true);
+        mScrollBar.setPadding(10, 20);
+
+        DefaultScrollBar defaultScrollBar = (DefaultScrollBar) mScrollBar;
+
+        assertThat(defaultScrollBar.mPaddingStart).isEqualTo(10);
+        assertThat(defaultScrollBar.mPaddingEnd).isEqualTo(20);
+    }
+
+    @Test
+    public void setPadding_shouldThrowErrorWithoutInitialization() {
+        assertThrows(NullPointerException.class, () -> mScrollBar.setPadding(10, 20));
+    }
+
+    @Test
+    public void requestLayout_shouldThrowErrorWithoutInitialization() {
+        assertThrows(NullPointerException.class, () -> mScrollBar.requestLayout());
+    }
+}
diff --git a/car-ui-lib/tests/robotests/src/com/android/car/ui/pagedrecyclerview/PagedSnapHelperTest.java b/car-ui-lib/tests/robotests/src/com/android/car/ui/pagedrecyclerview/PagedSnapHelperTest.java
new file mode 100644
index 0000000..ef6c5af
--- /dev/null
+++ b/car-ui-lib/tests/robotests/src/com/android/car/ui/pagedrecyclerview/PagedSnapHelperTest.java
@@ -0,0 +1,185 @@
+/*
+ * Copyright 2019 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.car.ui.pagedrecyclerview;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.graphics.PointF;
+import android.view.View;
+
+import androidx.recyclerview.widget.LinearLayoutManager;
+import androidx.recyclerview.widget.RecyclerView;
+
+import com.android.car.ui.CarUiRobolectricTestRunner;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.RuntimeEnvironment;
+import org.robolectric.annotation.Config;
+
+@RunWith(CarUiRobolectricTestRunner.class)
+@Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
+public class PagedSnapHelperTest {
+
+    private Context mContext;
+    private PagedSnapHelper mPagedSnapHelper;
+
+    @Mock
+    private RecyclerView mRecyclerView;
+    @Mock
+    private LinearLayoutManager mLayoutManager;
+    @Mock
+    private RecyclerView.Adapter mAdapter;
+    @Mock
+    private View mChild;
+    @Mock
+    private RecyclerView.LayoutParams mLayoutParams;
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mContext = RuntimeEnvironment.application;
+
+        mPagedSnapHelper = new PagedSnapHelper(mContext);
+
+        when(mRecyclerView.getContext()).thenReturn(mContext);
+        mPagedSnapHelper.attachToRecyclerView(mRecyclerView);
+    }
+
+    @Test
+    public void smoothScrollBy_invalidSnapPosition_shouldCallRecylerViewSmoothScrollBy() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+
+        mPagedSnapHelper.smoothScrollBy(10);
+
+        verify(mRecyclerView).smoothScrollBy(0, 10);
+    }
+
+    @Test
+    public void smoothScrollBy_invalidSnapPositionNoItem_shouldCallRecylerViewSmoothScrollBy() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(0);
+
+        mPagedSnapHelper.smoothScrollBy(10);
+
+        verify(mRecyclerView).smoothScrollBy(0, 10);
+    }
+
+    @Test
+    public void smoothScrollBy_invalidSnapPositionNoView_shouldCallRecylerViewSmoothScrollBy() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(10);
+        when(mLayoutManager.canScrollVertically()).thenReturn(false);
+        when(mLayoutManager.canScrollHorizontally()).thenReturn(false);
+
+        mPagedSnapHelper.smoothScrollBy(10);
+
+        verify(mRecyclerView).smoothScrollBy(0, 10);
+    }
+
+    @Test
+    public void smoothScrollBy_invalidSnapPositionNoVectore_shouldCallRecylerViewSmoothScrollBy() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(10);
+        when(mLayoutManager.canScrollVertically()).thenReturn(true);
+        when(mLayoutManager.getChildCount()).thenReturn(1);
+        when(mChild.getLayoutParams()).thenReturn(mLayoutParams);
+        when(mLayoutManager.getChildAt(0)).thenReturn(mChild);
+
+        mPagedSnapHelper.smoothScrollBy(10);
+
+        verify(mRecyclerView).smoothScrollBy(0, 10);
+    }
+
+    @Test
+    public void smoothScrollBy_invalidSnapPositionNoDelta_shouldCallRecylerViewSmoothScrollBy() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(1);
+        when(mLayoutManager.canScrollVertically()).thenReturn(true);
+        when(mLayoutManager.getChildCount()).thenReturn(1);
+        // no delta
+        when(mLayoutManager.getDecoratedBottom(any())).thenReturn(0);
+        when(mChild.getLayoutParams()).thenReturn(mLayoutParams);
+        when(mLayoutManager.getChildAt(0)).thenReturn(mChild);
+
+        PointF vectorForEnd = new PointF(100, 100);
+        when(mLayoutManager.computeScrollVectorForPosition(0)).thenReturn(vectorForEnd);
+
+        mPagedSnapHelper.smoothScrollBy(10);
+
+        verify(mRecyclerView).smoothScrollBy(0, 10);
+    }
+
+    @Test
+    public void smoothScrollBy_validSnapPosition_shouldCallRecylerViewSmoothScrollBy() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(1);
+        when(mLayoutManager.canScrollVertically()).thenReturn(true);
+        when(mLayoutManager.getChildCount()).thenReturn(1);
+        // some delta
+        when(mLayoutManager.getDecoratedBottom(any())).thenReturn(10);
+        when(mChild.getLayoutParams()).thenReturn(mLayoutParams);
+        when(mLayoutManager.getChildAt(0)).thenReturn(mChild);
+
+        PointF vectorForEnd = new PointF(100, 100);
+        when(mLayoutManager.computeScrollVectorForPosition(0)).thenReturn(vectorForEnd);
+
+        mPagedSnapHelper.smoothScrollBy(10);
+
+        verify(mLayoutManager).startSmoothScroll(any(RecyclerView.SmoothScroller.class));
+    }
+
+    @Test
+    public void calculateDistanceToFinalSnap_shouldReturnTopMarginDifference() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(1);
+        when(mLayoutManager.canScrollVertically()).thenReturn(true);
+        when(mLayoutManager.getChildCount()).thenReturn(1);
+        // some delta
+        when(mLayoutManager.getDecoratedTop(any())).thenReturn(10);
+        when(mChild.getLayoutParams()).thenReturn(mLayoutParams);
+
+        int[] distance = mPagedSnapHelper.calculateDistanceToFinalSnap(mLayoutManager, mChild);
+
+        assertThat(distance[1]).isEqualTo(10);
+    }
+
+    @Test
+    public void calculateScrollDistance_shouldScrollHeightOfView() {
+        when(mRecyclerView.getLayoutManager()).thenReturn(mLayoutManager);
+        when(mLayoutManager.getItemCount()).thenReturn(1);
+        when(mLayoutManager.canScrollVertically()).thenReturn(true);
+        when(mLayoutManager.getChildCount()).thenReturn(1);
+        // some delta
+        when(mLayoutManager.getDecoratedTop(any())).thenReturn(10);
+        when(mChild.getLayoutParams()).thenReturn(mLayoutParams);
+        when(mLayoutManager.getChildAt(0)).thenReturn(mChild);
+        when(mLayoutManager.getHeight()).thenReturn(-50);
+
+        int[] distance = mPagedSnapHelper.calculateScrollDistance(0, 10);
+
+        assertThat(distance[1]).isEqualTo(50);
+    }
+}