Make AarGeneratorAction worker compatible

AarGeneratorAction isn't currently worker compatible even though the `ResourceProcessorBusyBox` action supports the `supports-workers` execution requirements.

Closes #14144.

PiperOrigin-RevId: 405477763

src/tools/android/java/com/google/devtools/build/android/AarGeneratorAction.java

diff --git a/src/tools/android/java/com/google/devtools/build/android/AarGeneratorAction.java b/src/tools/android/java/com/google/devtools/build/android/AarGeneratorAction.java
index 939dfaf..b277fdc 100644
--- a/src/tools/android/java/com/google/devtools/build/android/AarGeneratorAction.java
+++ b/src/tools/android/java/com/google/devtools/build/android/AarGeneratorAction.java
@@ -159,7 +159,7 @@
     public boolean throwOnResourceConflict;
   }
 
-  public static void main(String[] args) {
+  public static void main(String[] args) throws IOException {
     Stopwatch timer = Stopwatch.createStarted();
     OptionsParser optionsParser =
         OptionsParser.builder()
@@ -205,12 +205,11 @@
           String.format("Packaging finished at %dms", timer.elapsed(TimeUnit.MILLISECONDS)));
     } catch (MergeConflictException e) {
       logger.log(Level.SEVERE, e.getMessage());
-      System.exit(1);
+      throw e;
     } catch (IOException | MergingException e) {
       logger.log(Level.SEVERE, "Error during merging resources", e);
-      System.exit(1);
+      throw e;
     }
-    System.exit(0);
   }
 
   @VisibleForTesting