r=valeski, exposing channel for 32604 Trunk fix for illegal use of nsString-external JavaScript

netwerk/base/public/nsIStreamLoader.idl

@@ -60,6 +60,12 @@ interface nsIStreamLoader : nsISupports
      * Gets the owner of this file
      */
     readonly attribute nsISupports owner;
+
+    /**
+     * Gets the channel
+     */
+    readonly attribute nsIChannel channel;
+
 };
 
 %{C++

netwerk/base/src/nsStreamLoader.cpp

@@ -104,6 +104,14 @@ nsStreamLoader::GetOwner(nsISupports** aOwner)
   return NS_OK;
 }
 
+NS_IMETHODIMP 
+nsStreamLoader::GetChannel(nsIChannel** aChannel)
+{
+  *aChannel = mChannel.get();
+  NS_IF_ADDREF(*aChannel);
+  return NS_OK;
+}
+
 NS_IMETHODIMP 
 nsStreamLoader::OnStartRequest(nsIChannel* channel, nsISupports *ctxt)
 {
@@ -115,6 +123,7 @@ nsStreamLoader::OnStopRequest(nsIChannel* channel, nsISupports *ctxt,
                               nsresult status, const PRUnichar *errorMsg)
 {
   (void)channel->GetOwner(getter_AddRefs(mOwner));
+  mChannel = channel;
   nsresult rv = mObserver->OnStreamComplete(this, mContext, status, 
                                             mData.Length(), 
                                             mData.GetBuffer());

netwerk/base/src/nsStreamLoader.h

@@ -48,6 +48,7 @@ protected:
   nsCOMPtr<nsISupports>             mContext;  // the observer's context
   nsCString                         mData;
   nsCOMPtr<nsISupports>             mOwner;
+  nsCOMPtr<nsIChannel>              mChannel;
 ///  nsCOMPtr<nsILoadGroup> mLoadGroup;
 };