diff --git a/services/surfaceflinger/BufferLayerConsumer.cpp b/services/surfaceflinger/BufferLayerConsumer.cpp
index ae3c96c..0303d94 100644
--- a/services/surfaceflinger/BufferLayerConsumer.cpp
+++ b/services/surfaceflinger/BufferLayerConsumer.cpp
@@ -143,6 +143,12 @@
     return mConsumer->setDefaultBufferSize(w, h);
 }
 
+void BufferLayerConsumer::setContentsChangedListener(const wp<ContentsChangedListener>& listener) {
+    setFrameAvailableListener(listener);
+    Mutex::Autolock lock(mMutex);
+    mContentsChangedListener = listener;
+}
+
 status_t BufferLayerConsumer::updateTexImage() {
     ATRACE_CALL();
     BLC_LOGV("updateTexImage");
@@ -549,6 +555,24 @@
     }
 }
 
+void BufferLayerConsumer::onSidebandStreamChanged() {
+    FrameAvailableListener* unsafeFrameAvailableListener = nullptr;
+    {
+        Mutex::Autolock lock(mFrameAvailableMutex);
+        unsafeFrameAvailableListener = mFrameAvailableListener.unsafe_get();
+    }
+    sp<ContentsChangedListener> listener;
+    { // scope for the lock
+        Mutex::Autolock lock(mMutex);
+        ALOG_ASSERT(unsafeFrameAvailableListener == mContentsChangedListener.unsafe_get());
+        listener = mContentsChangedListener.promote();
+    }
+
+    if (listener != NULL) {
+        listener->onSidebandStreamChanged();
+    }
+}
+
 void BufferLayerConsumer::addAndGetFrameTimestamps(const NewFrameEventsEntry* newTimestamps,
                                                    FrameEventHistoryDelta* outDelta) {
     sp<Layer> l = mLayer.promote();