Move to androidx packages

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

 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
@@ -11,7 +11,7 @@
         android:layout_height="wrap_content"
         app:layout_constraintTop_toTopOf="parent" />
 
-    <android.support.constraint.ConstraintLayout
+    <androidx.constraintlayout.widget.ConstraintLayout
         android:id="@+id/layout_container"
         android:layout_width="0dp"
         android:layout_height="0dp"
@@ -20,7 +20,7 @@
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toBottomOf="@id/toolbar_layout">
 
-        <android.support.design.chip.ChipGroup
+        <com.google.android.material.chip.ChipGroup
             android:id="@+id/members_chips"
             style="@style/Widget.MaterialComponents.Chip.Entry"
             android:layout_width="match_parent"
@@ -31,7 +31,7 @@
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toTopOf="parent">
 
-        </android.support.design.chip.ChipGroup>
+        </com.google.android.material.chip.ChipGroup>
 
         <com.wang.avi.AVLoadingIndicatorView
             android:id="@+id/view_loading"
@@ -63,12 +63,12 @@
             android:background="@color/colorDividerMessageComposer"
             app:layout_constraintTop_toBottomOf="@id/text_search_member" />
 
-        <android.support.v7.widget.RecyclerView
+        <androidx.recyclerview.widget.RecyclerView
             android:id="@+id/recycler_view"
             android:layout_width="match_parent"
             android:layout_height="0dp"
             android:scrollbars="vertical"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintTop_toBottomOf="@id/separator_1" />
-    </android.support.constraint.ConstraintLayout>
-</android.support.constraint.ConstraintLayout>
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file

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

 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.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:layout_width="match_parent"
@@ -41,4 +41,4 @@
         app:layout_constraintEnd_toEndOf="parent"
         app:layout_constraintTop_toTopOf="parent"
         tools:text="04/06/2018 14:18:36" />
-</android.support.constraint.ConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>

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

 <?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     android:id="@+id/toolbar_container"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
 
-    <android.support.v7.widget.Toolbar
+    <androidx.appcompat.widget.Toolbar
         android:id="@+id/toolbar"
         android:layout_width="match_parent"
         android:layout_height="@dimen/toolbar_height"
@@ -29,6 +29,6 @@
             android:gravity="end"
             android:textSize="14sp" />
 
-    </android.support.v7.widget.Toolbar>
+    </androidx.appcompat.widget.Toolbar>
 
-</android.support.constraint.ConstraintLayout>
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file