Fix stuck while disconnecting chromecast

[Description]
ACodec is stuck while disconnecting chromecast(mirror mode) playback
Solution:
add the buffer consuming flow in ConsumerListener::onFrameAvailable

Bug: 176522646

[Test Report]
CAST exit OK after disconnecting many times

Change-Id: Ic1fdec917dc435bbf86309d98efc5c76bb64ba42
diff --git a/media/libstagefright/MediaCodec.cpp b/media/libstagefright/MediaCodec.cpp
index 0ed0de1..49520c2 100644
--- a/media/libstagefright/MediaCodec.cpp
+++ b/media/libstagefright/MediaCodec.cpp
@@ -321,11 +321,24 @@
         BufferQueue::createBufferQueue(&mProducer, &mConsumer);
         mSurface = new Surface(mProducer, false /* controlledByApp */);
         struct ConsumerListener : public BnConsumerListener {
-            void onFrameAvailable(const BufferItem&) override {}
+            ConsumerListener(const sp<IGraphicBufferConsumer> &consumer) {
+                mConsumer = consumer;
+            }
+            void onFrameAvailable(const BufferItem&) override {
+                BufferItem buffer;
+                // consume buffer
+                sp<IGraphicBufferConsumer> consumer = mConsumer.promote();
+                if (consumer != nullptr && consumer->acquireBuffer(&buffer, 0) == NO_ERROR) {
+                    consumer->releaseBuffer(buffer.mSlot, buffer.mFrameNumber,
+                                            EGL_NO_DISPLAY, EGL_NO_SYNC_KHR, buffer.mFence);
+                }
+            }
+
+            wp<IGraphicBufferConsumer> mConsumer;
             void onBuffersReleased() override {}
             void onSidebandStreamChanged() override {}
         };
-        sp<ConsumerListener> listener{new ConsumerListener};
+        sp<ConsumerListener> listener{new ConsumerListener(mConsumer)};
         mConsumer->consumerConnect(listener, false);
         mConsumer->setConsumerName(String8{"MediaCodec.release"});
         mConsumer->setConsumerUsageBits(usage);