All players in one place

- main, background, popup players now connected via one service, one view, one fragment, one activity and one gesture listener
- playback position is synchronized between players. Easy to switch from one to another
- expandable player at the bottom of the screen with cool animation and additional features like long click to open channel of a video, play/pause/close buttons and swipe down to dismiss
- in-player integrated buttons for opening in browser, playing with Kodi, sharing a video
- better background playback that can be activated in settings. Allows to automatically switch to audio-only mode when going to background and then switching to video-mode when returning to the app.

app/src/main/res/layout/activity_main.xml

@@ -2,6 +2,7 @@
 <androidx.drawerlayout.widget.DrawerLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:id="@+id/drawer_layout"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
@@ -22,6 +23,23 @@
         <include layout="@layout/toolbar_layout" />
     </FrameLayout>
 
+    <androidx.coordinatorlayout.widget.CoordinatorLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content">
+
+        <FrameLayout
+                android:id="@+id/fragment_player_holder"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:layout_gravity="center_horizontal"
+                app:behavior_hideable="true"
+                app:behavior_peekHeight="0dp"
+                app:layout_behavior="org.schabi.newpipe.player.event.CustomBottomSheetBehavior">
+        </FrameLayout>
+
+    </androidx.coordinatorlayout.widget.CoordinatorLayout>
+
+
     <include layout="@layout/drawer_layout"/>
 
 </androidx.drawerlayout.widget.DrawerLayout>