Upgrade build tools to 26.0.2 and remote retrolambda

build.gradle

@@ -3,9 +3,6 @@ buildscript {
     repositories {
         mavenCentral()
     }
-    dependencies {
-        classpath 'me.tatarka:gradle-retrolambda:3.3.1'
-    }
 }
 
 repositories {
@@ -14,11 +11,10 @@ repositories {
 }
 
 apply plugin: 'com.android.library'
-apply plugin: 'me.tatarka.retrolambda'
 
 android {
     compileSdkVersion 25
-    buildToolsVersion "25.0.0"
+    buildToolsVersion '26.0.2'
 
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8