codec preferences: add missing constructor, fix margins

* fix crash due to missing constructor
* add proper margins
* fix warnings

Change-Id: I11ba072a494822d133521abc57e708236a3a57b7
diff --git a/ring-android/app/src/main/res/layout/item_codec.xml b/ring-android/app/src/main/res/layout/item_codec.xml
index 46c6670..a929405 100644
--- a/ring-android/app/src/main/res/layout/item_codec.xml
+++ b/ring-android/app/src/main/res/layout/item_codec.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?><!--
-Copyright (C) 2004-2016 Savoir-faire Linux Inc.
+Copyright (C) 2004-2018 Savoir-faire Linux Inc.
 
 Author: Adrien Béraud <adrien.beraud@savoirfairelinux.com>
 
@@ -28,22 +28,25 @@
         android:id="@+id/codec_name"
         android:layout_width="wrap_content"
         android:layout_height="?android:attr/listPreferredItemHeight"
+        android:layout_marginEnd="16dp"
+        android:layout_marginStart="16dp"
         android:gravity="center_vertical"
-        android:text="H.264"
         android:textColor="@color/text_color_primary"
-        android:textSize="16sp" />
+        android:textSize="16sp"
+        tools:text="H.264" />
 
     <TextView
         android:id="@+id/codec_samplerate"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_alignBaseline="@+id/codec_name"
+        android:layout_alignBaseline="@id/codec_name"
         android:layout_centerVertical="true"
         android:layout_toEndOf="@id/codec_name"
+        android:layout_toStartOf="@id/codec_checked"
         android:gravity="center_vertical"
-        android:text="32000"
         android:textColor="@color/text_color_secondary"
-        android:textSize="12sp" />
+        android:textSize="12sp"
+        tools:text="32000" />
 
     <CheckBox
         android:id="@+id/codec_checked"