diff --git a/netwerk/protocol/file/src/nsFileChannel.cpp b/netwerk/protocol/file/src/nsFileChannel.cpp
index fc98e7f8091..e74903f4e86 100644
--- a/netwerk/protocol/file/src/nsFileChannel.cpp
+++ b/netwerk/protocol/file/src/nsFileChannel.cpp
@@ -684,6 +684,12 @@ nsFileChannel::OnFull(nsIBuffer* buffer)
     return Suspend();
 }
 
+NS_IMETHODIMP
+nsFileChannel::OnWrite(nsIBuffer* aBuffer, PRUint32 aCount)
+{
+    return NS_OK;
+}
+
 NS_IMETHODIMP
 nsFileChannel::OnEmpty(nsIBuffer* buffer)
 {
diff --git a/netwerk/protocol/file/src/nsFileChannel.h b/netwerk/protocol/file/src/nsFileChannel.h
index aa7153e733a..845f4829c80 100644
--- a/netwerk/protocol/file/src/nsFileChannel.h
+++ b/netwerk/protocol/file/src/nsFileChannel.h
@@ -146,6 +146,8 @@ public:
 
     NS_IMETHOD OnFull(nsIBuffer* buffer);
 
+    NS_IMETHOD OnWrite(nsIBuffer* aBuffer, PRUint32 aCount);
+
     NS_IMETHOD OnEmpty(nsIBuffer* buffer);
 
     ////////////////////////////////////////////////////////////////////////////