How to fix these proguard warnings
<p>I am using a third party library in my project, since then proguard is issuing me these warnings, which I can't relate to that library, Here is the library I am using: <a href="https://github.com/OrangeGangsters/LolliPin" rel="nofollow noreferrer">Lollipin</a>.</p>

<p><strong>Warnings I am getting</strong></p>

<pre><code>Warning:android.databinding.DataBindingUtil: can't find referenced class android.databinding.DataBinderMapper
Warning:android.databinding.ViewDataBinding: can't find referenced class android.databinding.DataBinderMapper
Warning:there were 43 unresolved references to classes or interfaces.
Warning:Exception while processing task java.io.IOException: Please correct the above warnings first.
</code></pre>

<p><strong>What I have tried?</strong></p>

<p>I have edited <code>proguard-rules.pro</code> like this:</p>

<pre><code>-keeppackagenames com.github.orangegangsters.lollipin
</code></pre>

<p>Still no go! I have also tried to clean and rebuild project that also didn't work out.</p>

<p>Here is build.gradle:</p>

<pre><code>apply plugin: 'com.android.application'

 android {
compileSdkVersion 24
buildToolsVersion '24.0.2'

defaultConfig {
    applicationId "com.example.teach"
    minSdkVersion 15
    targetSdkVersion 24
    versionCode 27
    versionName "5.0"
}
buildTypes {
    release {

        minifyEnabled true
        shrinkResources true
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
    }

}


}

dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')

compile 'com.android.support:appcompat-v7:24.2.1'
compile('com.mikepenz:materialdrawer:5.6.0@aar') {
    transitive = true
}
compile ('com.github.orangegangsters:lollipin:2.0.0@aar') {
    transitive = true
}

 compile 'com.google.android.gms:play-services-ads:9.6.0'


}
apply plugin: 'com.google.gms.google-services'
</code></pre>