AsyncTask now uses the poll executor for apps up through HC MR1 and t…

…he serialized one after that.

Change-Id: I47d135ace5f8e78e4fa44ac9d1bf7abeeb9d3ba0

core/java/android/app/ActivityThread.java

@@ -45,6 +45,7 @@
 import android.net.IConnectivityManager;
 import android.net.Proxy;
 import android.net.ProxyProperties;
+import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Debug;
 import android.os.Handler;
@@ -3427,6 +3428,14 @@ private final void handleBindApplication(AppBindData data) {
         Process.setArgV0(data.processName);
         android.ddm.DdmHandleAppName.setAppName(data.processName);
 
+        // If the app is Honeycomb MR1 or earlier, switch its AsyncTask
+        // implementation to use the pool executor.  Normally, we use the
+        // serialized executor as the default. This has to happen in the
+        // main thread so the main looper is set right.
+        if (data.appInfo.targetSdkVersion <= 12) {
+            AsyncTask.setDefaultExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
+        }
+
         /*
          * Before spawning a new process, reset the time zone to be the system time zone.
          * This needs to be done because the system time zone could have changed after the

core/java/android/os/AsyncTask.java

@@ -153,7 +153,6 @@ public abstract class AsyncTask<Params, Progress, Result> {
     private static final int MAXIMUM_POOL_SIZE = 128;
     private static final int KEEP_ALIVE = 1;
 
-
     private static final ThreadFactory sThreadFactory = new ThreadFactory() {
         private final AtomicInteger mCount = new AtomicInteger(1);
 
@@ -183,6 +182,7 @@ public Thread newThread(Runnable r) {
 
     private static final InternalHandler sHandler = new InternalHandler();
 
+    private static volatile Executor sDefaultExecutor = SERIAL_EXECUTOR;
     private final WorkerRunnable<Params, Result> mWorker;
     private final FutureTask<Result> mFuture;
 
@@ -240,6 +240,11 @@ public static void init() {
         sHandler.getLooper();
     }
 
+    /** @hide */
+    public static void setDefaultExecutor(Executor exec) {
+        sDefaultExecutor = exec;
+    }
+
     /**
      * Creates a new asynchronous task. This constructor must be invoked on the UI thread.
      */
@@ -496,7 +501,7 @@ public final Result get(long timeout, TimeUnit unit) throws InterruptedException
      *         {@link AsyncTask.Status#RUNNING} or {@link AsyncTask.Status#FINISHED}.
      */
     public final AsyncTask<Params, Progress, Result> execute(Params... params) {
-        return executeOnExecutor(THREAD_POOL_EXECUTOR, params);
+        return executeOnExecutor(sDefaultExecutor, params);
     }
 
     /**
@@ -559,7 +564,7 @@ public final AsyncTask<Params, Progress, Result> executeOnExecutor(Executor exec
      * a simple Runnable object.
      */
     public static void execute(Runnable runnable) {
-        THREAD_POOL_EXECUTOR.execute(runnable);
+        sDefaultExecutor.execute(runnable);
     }
 
     /**