Correctly count acquired channels when timeout occurs in FixedChannelPool

Motivation:

We don't decrease acquired channel count in FixedChannelPool when timeout occurs by AcquireTimeoutAction.NEW and eventually fails.

Modifications:

Set AcquireTask.acquired=true to call decrementAndRunTaskQueue when timeout action fails.

Result:

Acquired channel count decreases correctly.

transport/src/main/java/io/netty/channel/pool/FixedChannelPool.java

@@ -153,7 +153,7 @@ public final class FixedChannelPool extends SimpleChannelPool {
                     public void onTimeout(AcquireTask task) {
                         // Increment the acquire count and delegate to super to actually acquire a Channel which will
                         // create a new connetion.
-                        ++acquiredChannelCount;
+                        task.acquired();
 
                         FixedChannelPool.super.acquire(task.promise);
                     }
@@ -191,14 +191,14 @@ public final class FixedChannelPool extends SimpleChannelPool {
         assert executor.inEventLoop();
 
         if (acquiredChannelCount < maxConnections) {
-            ++acquiredChannelCount;
-
-            assert acquiredChannelCount > 0;
+            assert acquiredChannelCount >= 0;
 
             // We need to create a new promise as we need to ensure the AcquireListener runs in the correct
             // EventLoop
             Promise<Channel> p = executor.newPromise();
-            p.addListener(new AcquireListener(promise));
+            AcquireListener l = new AcquireListener(promise);
+            l.acquired();
+            p.addListener(l);
             super.acquire(p);
         } else {
             if (pendingAcquireCount >= maxPendingAcquires) {
@@ -271,10 +271,8 @@ public final class FixedChannelPool extends SimpleChannelPool {
                 timeoutFuture.cancel(false);
             }
 
-            task.acquired();
-
             --pendingAcquireCount;
-            ++acquiredChannelCount;
+            task.acquired();
 
             super.acquire(task.promise);
         }
@@ -291,7 +289,7 @@ public final class FixedChannelPool extends SimpleChannelPool {
         ScheduledFuture<?> timeoutFuture;
 
         public AcquireTask(Promise<Channel> promise) {
-            super(promise, false);
+            super(promise);
             // We need to create a new promise as we need to ensure the AcquireListener runs in the correct
             // EventLoop.
             this.promise = executor.<Channel>newPromise().addListener(this);
@@ -327,12 +325,7 @@ public final class FixedChannelPool extends SimpleChannelPool {
         protected boolean acquired;
 
         AcquireListener(Promise<Channel> originalPromise) {
-            this(originalPromise, true);
-        }
-
-        protected AcquireListener(Promise<Channel> originalPromise, boolean acquired) {
             this.originalPromise = originalPromise;
-            this.acquired = acquired;
         }
 
         @Override
@@ -353,6 +346,10 @@ public final class FixedChannelPool extends SimpleChannelPool {
         }
 
         public void acquired() {
+            if (acquired) {
+                return;
+            }
+            acquiredChannelCount++;
             acquired = true;
         }
     }