Add proper experimental option to use a fork join pool.

RELNOTES: None
PiperOrigin-RevId: 277460008

src/main/java/com/google/devtools/build/lib/buildtool/BuildRequestOptions.java

diff --git a/src/main/java/com/google/devtools/build/lib/buildtool/BuildRequestOptions.java b/src/main/java/com/google/devtools/build/lib/buildtool/BuildRequestOptions.java
index c2331fb..9b8ea2f 100644
--- a/src/main/java/com/google/devtools/build/lib/buildtool/BuildRequestOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/buildtool/BuildRequestOptions.java
@@ -364,6 +364,15 @@
               + " will be evaluated as a unit on Skyframe.")
   public int nestedSetAsSkyKeyThreshold;
 
+  @Option(
+      name = "experimental_use_fork_join_pool",
+      defaultValue = "false",
+      documentationCategory = OptionDocumentationCategory.UNDOCUMENTED,
+      metadataTags = OptionMetadataTag.EXPERIMENTAL,
+      effectTags = {OptionEffectTag.EXECUTION},
+      help = "If this flag is set, use a fork join pool in the abstract queue visitor.")
+  public boolean useForkJoinPool;
+
   /**
    * Converter for jobs: Takes keyword ({@value #FLAG_SYNTAX}). Values must be between 1 and
    * MAX_JOBS.

src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
index cafe901..b9a54a9 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
@@ -1558,6 +1558,7 @@
           EvaluationContext.newBuilder()
               .setKeepGoing(options.getOptions(KeepGoingOption.class).keepGoing)
               .setNumThreads(options.getOptions(BuildRequestOptions.class).jobs)
+              .setUseForkJoinPool(options.getOptions(BuildRequestOptions.class).useForkJoinPool)
               .setEventHander(reporter)
               .build();
       return buildDriver.evaluate(