title: Build Error -Ionic Cordova fails for android
body: <p>I get following error while running the command "ionic cordova build android --stacktrace" :</p>
  
  <pre><code>:generateDebugResources
  :mergeDebugResources
  
  :processDebugManifest
  
  :processDebugResources
  ERROR: In &lt;declare-styleable&gt; FontFamilyFont, unable to find attribute android:fontVariationSettings
   FAILED
  ERROR: In &lt;declare-styleable&gt; FontFamilyFont, unable to find attribute android:ttcIndex
  
  I am using following tools on Window's:
   Editor : VScode
  
  Ionic: C:\Users\xyz&gt;ionic -version
  3.19.1
  Npm as packagemanager
  </code></pre>
  
  <p>Project Properties: </p>
  
  <pre><code>target=android-26
  cordova.system.library.1=com.google.android.gms:play-services-analytics:+
  cordova.system.library.2=com.facebook.android:facebook-android-sdk:4.+
  cordova.gradle.include.1=cordova-plugin-appsflyer-sdk/customerapp-cordovaAF.gradle
  cordova.gradle.include.2=twitter-connect-plugin/customerapp-twitter.gradle
  cordova.system.library.3=com.android.support:support-v4:26.+
  cordova.system.library.4=com.android.support:appcompat-v7:26.+
  cordova.system.library.5=com.android.support:support-v4:24.1.1+
  cordova.system.library.6=com.android.support:support-v4:+
  android.library.reference.1=CordovaLib
  </code></pre>