Kotlin Data binding nullability

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>
        <variable name="weather" type="org.example.kotlin.databinding.WeatherData" />
    </data>
    <LinearLayout
        android:orientation="vertical"
        android:layout_margin="4dp"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <TextView android:layout_width="match_parent" android:layout_height="wrap_content"
            android:text="@{weather.location}"
            android:textSize="18sp" />
        <TextView android:layout_width="match_parent" android:layout_height="wrap_content"
            android:text="@{weather.temperature}" />
        <TextView android:layout_width="match_parent" android:layout_height="wrap_content"
            android:text="@{weather.info}" />
        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@{weather.imageUrl}"
            android:contentDescription="@string/image" />

        <Button
            android:text="@string/change"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:onClick="changeTemperatureAndImage" />

        <Button
            android:text="@string/next"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:onClick="startActivity" />

    </LinearLayout>
</layout>

ActivityMainBinding.java

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package org.example.kotlin.databinding.databinding;

import android.databinding.DataBindingComponent;
import android.databinding.DataBindingUtil;
import android.databinding.ViewDataBinding;
import android.databinding.ViewDataBinding.IncludedLayouts;
import android.databinding.adapters.TextViewBindingAdapter;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.SparseIntArray;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import org.example.kotlin.databinding.ImageBindingAdapter;
import org.example.kotlin.databinding.WeatherData;

public class ActivityMainBinding extends ViewDataBinding {
    @Nullable
    private static final IncludedLayouts sIncludes = null;
    @Nullable
    private static final SparseIntArray sViewsWithIds = null;
    @NonNull
    private final LinearLayout mboundView0;
    @NonNull
    private final TextView mboundView1;
    @NonNull
    private final TextView mboundView2;
    @NonNull
    private final TextView mboundView3;
    @NonNull
    private final ImageView mboundView4;
    @Nullable
    private WeatherData mData;
    private long mDirtyFlags = -1L;

    public ActivityMainBinding(@NonNull DataBindingComponent bindingComponent, @NonNull View root) {
        super(bindingComponent, root, 1);
        Object[] bindings = mapBindings(bindingComponent, root, 5, sIncludes, sViewsWithIds);
        this.mboundView0 = (LinearLayout)bindings[0];
        this.mboundView0.setTag((Object)null);
        this.mboundView1 = (TextView)bindings[1];
        this.mboundView1.setTag((Object)null);
        this.mboundView2 = (TextView)bindings[2];
        this.mboundView2.setTag((Object)null);
        this.mboundView3 = (TextView)bindings[3];
        this.mboundView3.setTag((Object)null);
        this.mboundView4 = (ImageView)bindings[4];
        this.mboundView4.setTag((Object)null);
        this.setRootTag(root);
        this.invalidateAll();
    }

    public void invalidateAll() {
        synchronized(this) {
            this.mDirtyFlags = 2L;
        }

        this.requestRebind();
    }

    public boolean hasPendingBindings() {
        synchronized(this) {
            return this.mDirtyFlags != 0L;
        }
    }

    public boolean setVariable(int variableId, @Nullable Object variable) {
        boolean variableSet = true;
        if (1 == variableId) {
            this.setData((WeatherData)variable);
        } else {
            variableSet = false;
        }

        return variableSet;
    }

    public void setData(@Nullable WeatherData Data) {
        this.updateRegistration(0, Data);
        this.mData = Data;
        synchronized(this) {
            this.mDirtyFlags |= 1L;
        }

        this.notifyPropertyChanged(1);
        super.requestRebind();
    }

    @Nullable
    public WeatherData getData() {
        return this.mData;
    }

    protected boolean onFieldChange(int localFieldId, Object object, int fieldId) {
        switch(localFieldId) {
        case 0:
            return this.onChangeData((WeatherData)object, fieldId);
        default:
            return false;
        }
    }

    private boolean onChangeData(WeatherData Data, int fieldId) {
        if (fieldId == 0) {
            synchronized(this) {
                this.mDirtyFlags |= 1L;
                return true;
            }
        } else {
            return false;
        }
    }

    protected void executeBindings() {
        long dirtyFlags = 0L;
        synchronized(this) {
            dirtyFlags = this.mDirtyFlags;
            this.mDirtyFlags = 0L;
        }

        String dataTemperature = null;
        String dataImageUrl = null;
        WeatherData data = this.mData;
        String dataLocation = null;
        String dataInfo = null;
        if ((dirtyFlags & 3L) != 0L && data != null) {
            dataTemperature = data.getTemperature();
            dataImageUrl = data.getImageUrl();
            dataLocation = data.getLocation();
            dataInfo = data.getInfo();
        }

        if ((dirtyFlags & 3L) != 0L) {
            TextViewBindingAdapter.setText(this.mboundView1, dataLocation);
            TextViewBindingAdapter.setText(this.mboundView2, dataTemperature);
            TextViewBindingAdapter.setText(this.mboundView3, dataInfo);
            ImageBindingAdapter.setImageUrl(this.mboundView4, dataImageUrl);
        }

    }

    @NonNull
    public static ActivityMainBinding inflate(@NonNull LayoutInflater inflater, @Nullable ViewGroup root, boolean attachToRoot) {
        return inflate(inflater, root, attachToRoot, DataBindingUtil.getDefaultComponent());
    }

    @NonNull
    public static ActivityMainBinding inflate(@NonNull LayoutInflater inflater, @Nullable ViewGroup root, boolean attachToRoot, @Nullable DataBindingComponent bindingComponent) {
        return (ActivityMainBinding)DataBindingUtil.inflate(inflater, 2131296283, root, attachToRoot, bindingComponent);
    }

    @NonNull
    public static ActivityMainBinding inflate(@NonNull LayoutInflater inflater) {
        return inflate(inflater, DataBindingUtil.getDefaultComponent());
    }

    @NonNull
    public static ActivityMainBinding inflate(@NonNull LayoutInflater inflater, @Nullable DataBindingComponent bindingComponent) {
        return bind(inflater.inflate(2131296283, (ViewGroup)null, false), bindingComponent);
    }

    @NonNull
    public static ActivityMainBinding bind(@NonNull View view) {
        return bind(view, DataBindingUtil.getDefaultComponent());
    }

    @NonNull
    public static ActivityMainBinding bind(@NonNull View view, @Nullable DataBindingComponent bindingComponent) {
        if (!"layout/activity_main_0".equals(view.getTag())) {
            throw new RuntimeException("view tag isn't correct on view:" + view.getTag());
        } else {
            return new ActivityMainBinding(bindingComponent, view);
        }
    }
}

MainActivity.kt

package org.example.kotlin.databinding

import android.databinding.DataBindingUtil
import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import android.view.View
import org.example.kotlin.databinding.databinding.ActivityMainBinding
import org.jetbrains.anko.startActivity


class MainActivity : AppCompatActivity() {
    
    var counter = 1
    lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
         binding = DataBindingUtil.setContentView(this, R.layout.activity_main)

        binding.weather = WeatherData(
                "Saint Petersburg",
                "10 °C",
                "Cloudy with rain and possible thunderstorms",
                "http://loremflickr.com/800/600/city")
    }

    fun changeTemperatureAndImage(view: View) {
        ++counter

        binding.apply {
            weather.temperature = "$counter c"; // This is a compile error
          // See line 98 in ActivityMainBinding for the declaration of the getWeather method.
        }
    }

    fun startActivity(view: View) = startActivity<OtherActivity>()
}