Merge branch '6.x' of https://github.com/elastic/elasticsearch into 6.x

Author: astefan

buildSrc/build.gradle

@@ -24,15 +24,6 @@ plugins {
   id 'groovy'
 }
 
-gradlePlugin {
-  plugins {
-    simplePlugin {
-      id = 'elasticsearch.clusterformation'
-      implementationClass = 'org.elasticsearch.gradle.clusterformation.ClusterformationPlugin'
-    }
-  }
-}
-
 group = 'org.elasticsearch.gradle'
 
 String minimumGradleVersion = file('src/main/resources/minimumGradleVersion').text.trim()

buildSrc/src/main/groovy/org/elasticsearch/gradle/BuildPlugin.groovy

@@ -211,7 +211,7 @@ class BuildPlugin implements Plugin<Project> {
             project.rootProject.ext.minimumRuntimeVersion = minimumRuntimeVersion
             project.rootProject.ext.inFipsJvm = inFipsJvm
             project.rootProject.ext.gradleJavaVersion = JavaVersion.toVersion(gradleJavaVersion)
-            project.rootProject.ext.java9Home = findJavaHome("9")
+            project.rootProject.ext.java9Home = "${-> findJavaHome("9")}"
         }
 
         project.targetCompatibility = project.rootProject.ext.minimumRuntimeVersion

buildSrc/src/main/java/org/elasticsearch/gradle/precommit/ForbiddenApisCliTask.java

@@ -51,7 +51,8 @@ public class ForbiddenApisCliTask extends DefaultTask {
     private JavaVersion targetCompatibility;
     private FileCollection classesDirs;
     private SourceSet sourceSet;
-    private String javaHome;
+    // This needs to be an object so it can hold Groovy GStrings
+    private Object javaHome;
 
     @Input
     public JavaVersion getTargetCompatibility() {
@@ -142,11 +143,11 @@ public Configuration getForbiddenAPIsConfiguration() {
     }
 
     @Input
-    public String getJavaHome() {
+    public Object getJavaHome() {
         return javaHome;
     }
 
-    public void setJavaHome(String javaHome) {
+    public void setJavaHome(Object javaHome) {
         this.javaHome = javaHome;
     }
 

buildSrc/src/main/resources/META-INF/gradle-plugins/elasticsearch.clusterformation.properties

@@ -0,0 +1 @@
+implementation-class=org.elasticsearch.gradle.clusterformation.ClusterformationPlugin