For #631 - Adds license and dimen

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

@@ -1,4 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
 <androidx.cardview.widget.CardView
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
@@ -17,14 +20,14 @@
         xmlns:app="http://schemas.android.com/apk/res-auto"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:paddingBottom="16dp">
+        android:paddingBottom="@dimen/session_card_padding">
 
         <ImageView
             android:id="@+id/session_card_thumbnail"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:src="@drawable/ic_session_thumbnail_placeholder_blue"
-            android:layout_margin="16dp"
+            android:layout_margin="@dimen/session_card_padding"
             app:layout_constraintTop_toTopOf="parent"
             app:layout_constraintStart_toStartOf="parent"/>
 

app/src/main/res/values/dimens.xml

@@ -12,4 +12,5 @@
     <dimen name="library_item_icon_margin_horizontal">16dp</dimen>
     <dimen name="library_item_icon_margin_vertical">8dp</dimen>
     <dimen name="history_favicon_width_height">40dp</dimen>
+    <dimen name="session_card_padding">16dp</dimen>
 </resources>