Add worker support to []SingleJar.

RELNOTES:
Add worker support to []SingleJar.

--
MOS_MIGRATED_REVID=131133478
diff --git a/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJar.java b/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJar.java
index d99d84b..a7b7a10 100644
--- a/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJar.java
+++ b/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJar.java
@@ -411,7 +411,7 @@
     workerClass.getMethod("main", String[].class).invoke(null, (Object) args);
   }
 
-  private static boolean shouldRunInWorker(String[] args) {
+  protected static boolean shouldRunInWorker(String[] args) {
     return Arrays.asList(args).contains("--persistent_worker");
   }
 
diff --git a/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJarWorker.java b/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJarWorker.java
index 499192f..95554a8 100644
--- a/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJarWorker.java
+++ b/src/java_tools/singlejar/java/com/google/devtools/build/singlejar/SingleJarWorker.java
@@ -34,7 +34,7 @@
   private PrintStream originalSterr;
   private ByteArrayOutputStream stdoutAndStderr;
 
-  private void runWorker() {
+  protected void runWorker() {
     trapOutputs();
 
     try {
@@ -81,7 +81,7 @@
 
   private int runSingleJar(String[] args) {
     try {
-      return SingleJar.singleRun(args);
+      return singleRun(args);
     } catch (IOException e) {
       // Some IO failures are okay no need to quit the worker
       System.err.println("SingleJar threw exception : " + e.getMessage());
@@ -94,4 +94,8 @@
       return 1;
     }
   }
+
+  protected int singleRun(String[] args) throws Exception {
+    return SingleJar.singleRun(args);
+  }
 }