Switch to CoordinatorLayout for activity container

Snackbars use it to infer the right margins

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

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

@@ -1,10 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/master_detail_wrapper"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".activity.MainActivity">
+    tools:context=".activity.MainActivity"
+    android:fitsSystemWindows="true">
 
     <androidx.fragment.app.FragmentContainerView
         android:id="@+id/detail_container"
@@ -12,4 +13,4 @@
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:tag="LIST"/>
-</FrameLayout>
+</androidx.coordinatorlayout.widget.CoordinatorLayout>