Issue 4248 - Add codestyle check

libadblockplus-android-tests/build.gradle

 apply plugin: 'com.android.application'
+apply plugin: 'checkstyle'
 
 allprojects {
-  repositories {
-    mavenLocal()
-    mavenCentral()
-  }
+    repositories {
+        mavenLocal()
+        mavenCentral()
+    }
 }
 
 repositories {
-  mavenLocal()
-  mavenCentral()
+    mavenLocal()
+    mavenCentral()
 }
 
 android {
-  compileSdkVersion 16
-  buildToolsVersion "25.0.0"
+    compileSdkVersion 16
+    buildToolsVersion "25.0.0"
 
-  defaultConfig {
-    applicationId "org.adblockplus.libadblockplus.tests"
-    minSdkVersion 11
-    targetSdkVersion 16
-    versionCode 1
-    versionName "1.0"
-  }
-
-  sourceSets {
-    main {
-      manifest.srcFile 'AndroidManifest.xml'
+    defaultConfig {
+        applicationId "org.adblockplus.libadblockplus.tests"
+        minSdkVersion 11
+        targetSdkVersion 16
+        versionCode 1
+        versionName "1.0"
     }
 
-    androidTest {
-      manifest.srcFile 'AndroidManifest.xml'
-      java.srcDirs = ['src']
+    sourceSets {
+        main {
+            manifest.srcFile 'AndroidManifest.xml'
+        }
 
-      jni {
-        dependencies {
-          project ":libadblockplus-android"
+        androidTest {
+            manifest.srcFile 'AndroidManifest.xml'
+            java.srcDirs = ['src']
+
+            jni {
+                dependencies {
+                    project ":libadblockplus-android"
+                }
+            }
         }
-      }
     }
-  }
 }
 
 dependencies {
-  androidTestCompile project(':libadblockplus-android')
-  androidTestCompile fileTree(include: ['*.jar'], dir: 'libs')
+    androidTestCompile project(':libadblockplus-android')
+    androidTestCompile fileTree(include: ['*.jar'], dir: 'libs')
+}
+
+checkstyle {
+    toolVersion = '6.19'
+}
+
+task checkstyleMain(type: Checkstyle) {
+    ignoreFailures = true
+    showViolations = true
+    source 'src/org/adblockplus/'
+    exclude '**/gen/**'
+    exclude '**/R.java'
+    exclude '**/BuildConfig.java'
+    reports {
+        xml.destination "$project.buildDir/reports/checkstyle/main.xml"
+    }
+    classpath = files()
+    configFile = file("${rootProject.rootDir}/third_party/checkstyle/java/rules/eyeo_test_checks.xml")
+    configProperties = [
+            "checkstyle.header.file" : file("${rootProject.rootDir}/third_party/checkstyle/java/res/header.txt")
+    ]
 }