Fix gradle build

PrebidMobile/publisher.gradle

@@ -2,14 +2,18 @@ task javadoc(type: Javadoc, dependsOn: assemble) {
     source = android.sourceSets.main.java.srcDirs
     source += file('build/generated/source/buildConfig/release/org/prebid/mobile/core/BuildConfig.java').path
 
-    classpath += project.files(android.getBootClasspath().join(File.pathSeparator))
+    classpath += project.files(project.android.getBootClasspath())
 
     options.addBooleanOption('-ignore-source-errors', true)
     options.addStringOption('Xdoclint:none', '-quiet')
     options.addStringOption('encoding', 'UTF-8')
     options.addStringOption('charSet', 'UTF-8')
+    afterEvaluate {
+        tasks.javadoc.classpath += files(project.android.getBootClasspath())
+    }
 }
 
+
 task javadocJar(type: Jar, dependsOn: javadoc) {
     archiveClassifier.set("javadoc")
     from javadoc.destinationDir
@@ -18,4 +22,4 @@ task javadocJar(type: Jar, dependsOn: javadoc) {
 task sourcesJar(type: Jar) {
     archiveClassifier.set("sources")
     from android.sourceSets.main.java.srcDirs
-}
+}

gradlew.bat

@@ -64,6 +64,7 @@ set CMD_LINE_ARGS=%*
 @rem Setup the command line
 
 set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+CLASSPATH += files("${android.sdkDirectory}/platforms/${android.compileSdkVersion}/android.jar")
 
 @rem Execute Gradle
 "%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%