The patch for RT-37410 [Android] Add option to build to use retrolambda to remove lambdas added am hardcoded path to rt.jar.

The following patch fixes it:
diff --git a/buildSrc/dalvik.gradle b/buildSrc/dalvik.gradle
--- a/buildSrc/dalvik.gradle
+++ b/buildSrc/dalvik.gradle
@@ -236,7 +236,7 @@
                     classpath = configurations.retroconfig
                     main = 'net.orfjackal.retrolambda.Main'
                     jvmArgs = [
- "-Xbootclasspath:/opt/java/jre/lib/rt.jar",
+ "-Xbootclasspath:$JDK_HOME/jre/lib/rt.jar",
                                 "-Dretrolambda.inputDir=$inputdir",
                                 "-Dretrolambda.classpath=$basecp",
                                 "-Dretrolambda.bytecodeVersion=51",