Group/Room list : show filtered room when a group is selected

app/src/main/res/drawable/fg_group_item.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<selector xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <item android:state_selected="true">
+        <shape android:shape="oval">
+            <solid android:color="@android:color/transparent" />
+            <stroke android:width="2dp" android:color="@color/pale_teal" />
+        </shape>
+
+    </item>
+    <item android:drawable="@android:color/transparent" />
+
+</selector>

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

@@ -7,7 +7,7 @@
 
     <FrameLayout
         android:id="@+id/groupListFragmentContainer"
-        android:layout_width="56dp"
+        android:layout_width="64dp"
         android:layout_height="match_parent" />
 
     <FrameLayout

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

@@ -12,9 +12,11 @@
 
     <ImageView
         android:id="@+id/groupAvatarImageView"
-        android:layout_width="40dp"
-        android:layout_height="40dp"
+        android:layout_width="48dp"
+        android:layout_height="48dp"
         android:layout_gravity="center"
+        android:duplicateParentState="true"
+        android:foreground="@drawable/fg_group_item"
         tools:src="@tools:sample/avatars" />
 
 </im.vector.riotredesign.core.platform.CheckableFrameLayout>

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

@@ -2,15 +2,17 @@
 <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/roomCategoryRootView"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
+    android:background="?attr/selectableItemBackground"
     android:clickable="true"
     android:focusable="true"
-    android:id="@+id/roomCategoryRootView"
     android:gravity="center_vertical"
-    android:minHeight="24dp"
-    android:padding="16dp"
-    android:background="?attr/selectableItemBackground"
+    android:paddingLeft="16dp"
+    android:paddingTop="8dp"
+    android:paddingRight="16dp"
+    android:paddingBottom="8dp"
     tools:background="@color/pale_grey">
 
     <TextView