Some kotlin cosmetic tweaks (#157)

experimental/add_to_app/android_using_plugin/app/build.gradle

@@ -30,8 +30,8 @@ dependencies {
     implementation project(':flutter')
     implementation fileTree(dir: 'libs', include: ['*.jar'])
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
-    implementation 'androidx.appcompat:appcompat:1.0.2'
-    implementation 'androidx.core:core-ktx:1.0.2'
+    implementation 'androidx.appcompat:appcompat:1.1.0'
+    implementation 'androidx.core:core-ktx:1.1.0'
     implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
     testImplementation 'junit:junit:4.12'
     androidTestImplementation 'androidx.test.ext:junit:1.1.0'

experimental/add_to_app/android_using_plugin/app/src/main/java/dev/flutter/example/androidusingplugin/MainActivity.kt

@@ -11,14 +11,13 @@ import androidx.appcompat.app.AppCompatActivity
 import io.flutter.embedding.android.FlutterActivity
 
 class MainActivity : AppCompatActivity() {
-    private var counterLabel: TextView? = null
+    private lateinit var counterLabel: TextView
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
 
         counterLabel = findViewById(R.id.counter_label)
-
         val button = findViewById<Button>(R.id.launch_button)
 
         button.setOnClickListener {
@@ -32,6 +31,6 @@ class MainActivity : AppCompatActivity() {
     override fun onResume() {
         super.onResume()
         val app = application as MyApplication
-        counterLabel?.text = "Current count: ${app.count}"
+        counterLabel.text = "Current count: ${app.count}"
     }
 }

experimental/add_to_app/android_using_plugin/app/src/main/java/dev/flutter/example/androidusingplugin/MyApplication.kt

@@ -16,7 +16,7 @@ const val ENGINE_ID = "1"
 class MyApplication : Application() {
     var count = 0
 
-    private var channel: MethodChannel? = null
+    private lateinit var channel: MethodChannel
 
     override fun onCreate() {
         super.onCreate()
@@ -34,7 +34,7 @@ class MyApplication : Application() {
 
         channel = MethodChannel(flutterEngine.dartExecutor, "dev.flutter.example/counter")
 
-        channel?.setMethodCallHandler { call, _ ->
+        channel.setMethodCallHandler { call, _ ->
             when (call.method) {
                 "incrementCounter" -> {
                     count++
@@ -48,6 +48,6 @@ class MyApplication : Application() {
     }
 
     private fun reportCounter() {
-        channel?.invokeMethod("reportCounter", count)
+        channel.invokeMethod("reportCounter", count)
     }
 }