Sound panel doesn't match material next design for Android S

-title layout/margin/font size adjustment
-remove panel gap on left and right sides
-apply round corner 28dp only on top two corners

Bug: 191317779
Test: make -j50 RunSettingsRoboTests
Change-Id: I8ebd9238a7e746a48ae6baa4361600b5a21446c1

res/drawable/settings_panel_rounded_top_corner_background.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2021 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.
+-->
+
+<inset xmlns:android="http://schemas.android.com/apk/res/android">
+    <shape android:shape="rectangle">
+        <corners
+            android:topLeftRadius="@dimen/settings_panel_corner_radius"
+            android:topRightRadius="@dimen/settings_panel_corner_radius"
+            android:bottomLeftRadius="0dp"
+            android:bottomRightRadius="0dp"/>
+        <solid android:color="?android:attr/colorBackground" />
+    </shape>
+</inset>

res/layout/panel_layout.xml

@@ -20,7 +20,7 @@
     android:id="@+id/panel_container"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
-    android:background="@drawable/settings_panel_background" >
+    android:background="@drawable/settings_panel_rounded_top_corner_background" >
 
     <LinearLayout
         android:layout_width="match_parent"
@@ -30,7 +30,11 @@
         <LinearLayout
             android:id="@+id/panel_header"
             android:layout_width="match_parent"
-            android:layout_height="94dp"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="@dimen/settings_panel_title_margin"
+            android:layout_marginEnd="@dimen/settings_panel_title_margin"
+            android:layout_marginTop="@dimen/settings_panel_title_margin"
+            android:layout_marginBottom="@dimen/settings_panel_title_margin"
             android:gravity="start|center_vertical"
             android:orientation="horizontal"
             android:visibility="gone">
@@ -51,14 +55,13 @@
                 android:id="@+id/header_layout"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
-                android:layout_marginStart="16dp"
-                android:layout_marginEnd="16dp"
                 android:orientation="vertical">
 
                 <TextView
                     android:id="@+id/header_title"
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
+                    android:layout_marginBottom="8dp"
                     android:ellipsize="end"
                     android:maxLines="1"
                     android:textColor="?android:attr/textColorPrimary"
@@ -81,11 +84,12 @@
             android:id="@+id/panel_title"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            android:layout_marginTop="@dimen/settings_panel_title_margin"
+            android:layout_marginBottom="@dimen/settings_panel_title_margin"
             android:gravity="center"
-            android:paddingBottom="24dp"
-            android:paddingTop="18dp"
             android:textColor="?android:attr/textColorPrimary"
-            android:textSize="20sp"/>
+            android:textSize="24sp"
+            android:fontFamily="sans-serif-reqular"/>
 
         <ProgressBar
             android:id="@+id/progress_bar"

res/values/dimens.xml

@@ -427,6 +427,10 @@
     <dimen name="output_switcher_panel_icon_size">52dp</dimen>
     <dimen name="output_switcher_panel_icon_corner_radius">16dp</dimen>
 
+    <!-- Settings panel related dimensions -->
+    <dimen name="settings_panel_corner_radius">28dp</dimen>
+    <dimen name="settings_panel_title_margin">24dp</dimen>
+
     <!-- Text padding for EmptyTextSettings -->
     <dimen name="empty_text_padding">24dp</dimen>