Updated to Android studio 3 and am now getting the following error
Error:/app/build/intermediates/res/merged/debug/values/com_crashlytics_build_id.xml uncompiled XML file passed as argument. Must be compiled first into .flat file.
Error:java.util.concurrent.ExecutionException: com.android.builder.internal.aapt.AaptException: AAPT2 link failed: