Update Kotlin, gradle; remove unnecessary lateinit

build.gradle

 
 buildscript {
-    ext.kotlin_version = '1.2.41'
+    ext.kotlin_version = '1.2.50'
     ext.dokka_version = '0.9.16'
 
     repositories {

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.8-all.zip

src/main/java/at/bitfire/ical4android/BatchOperation.kt

@@ -18,7 +18,7 @@ class BatchOperation(
 ) {
 
     private val queue = LinkedList<Operation>()
-    private lateinit var results: Array<ContentProviderResult?>
+    private var results = arrayOfNulls<ContentProviderResult?>(0)
 
 
     fun nextBackrefIdx() = queue.size