updating template with custom drawable - more info

Adding the edit_text.xml custom drawable to the android template to fix
Null Pointer Exception Runtime Error from #17530
The template will include the following settings in new reactnative
applications, more info on the issue, the cause of the error and the solution
in commit 0858d41

template/android/app/src/main/res/drawable/edit_text.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<inset xmlns:android="http://schemas.android.com/apk/res/android"
+       android:insetLeft="@dimen/abc_edit_text_inset_horizontal_material"
+       android:insetRight="@dimen/abc_edit_text_inset_horizontal_material"
+       android:insetTop="@dimen/abc_edit_text_inset_top_material"
+       android:insetBottom="@dimen/abc_edit_text_inset_bottom_material">
+
+    <selector>
+        <item android:state_enabled="false" android:drawable="@drawable/abc_textfield_default_mtrl_alpha"/>
+        <item android:drawable="@drawable/abc_textfield_activated_mtrl_alpha"/>
+    </selector>
+
+</inset>

template/android/app/src/main/res/values/styles.xml

@@ -4,6 +4,7 @@
     <style name="AppTheme" parent="Theme.AppCompat.DayNight.NoActionBar">
         <!-- Customize your theme here. -->
         <item name="android:textColor">#000000</item>
+        <item name="android:editTextBackground">@drawable/edit_text</item>
     </style>
 
 </resources>