WIP on 40449, a/r=gagan

docshell/base/nsWebShell.cpp

@@ -1352,8 +1352,11 @@ nsWebShell::OnStartURLLoad(nsIDocumentLoader* loader,
 
   // Stop loading of the earlier document completely when the document url
   // load starts.  Now we know that this url is valid and available.
+  nsLoadFlags loadFlags = 0;
+  channel -> GetLoadAttributes (&loadFlags);
+
   PRBool equals = PR_FALSE;
-  if (NS_SUCCEEDED(aURL->Equals(mCurrentURI, &equals)) && equals)
+  if (NS_SUCCEEDED(aURL->Equals(mCurrentURI, &equals)) && equals && !(loadFlags & nsIChannel::LOAD_REPLACE))
     Stop();
 
   /*

netwerk/base/public/nsIChannel.idl

@@ -277,6 +277,12 @@ interface nsIChannel : nsIRequest
     const unsigned long VALIDATE_ONCE_PER_SESSION  = 1 << 14;
     const unsigned long VALIDATE_HEURISTICALLY     = 1 << 15;
 
+	/**
+	 * This flag is used to tell the webshell not to cancel the load in cases
+	 * when the channel is receiving multipart/replace document
+	 */
+	const unsigned long LOAD_REPLACE			   = 1 << 16;
+
     ////////////////////////////////////////////////////////////////////////////
     // nsIChannel operations
     ////////////////////////////////////////////////////////////////////////////

netwerk/streamconv/converters/nsMultiMixedConv.cpp

@@ -323,8 +323,8 @@ nsMultiMixedConv::BuildURI(nsIChannel *aChannel, nsIURI **_retval) {
     if (NS_FAILED(rv)) return rv;
 
     nsCAutoString dummyURIStr(uriSpec);
-    dummyURIStr.Append("##");
-    dummyURIStr.AppendInt(mPartCount, 10 /* radix */);
+//    dummyURIStr.Append("##");
+//    dummyURIStr.AppendInt(mPartCount, 10 /* radix */);
 
     return mIOService->NewURI(dummyURIStr.GetBuffer(), nsnull, _retval);
 }
@@ -349,8 +349,10 @@ nsMultiMixedConv::SendStart(nsIChannel *aChannel) {
 
     // First build up a dummy uri.
     nsCOMPtr<nsIURI> partURI;
-    rv = BuildURI(aChannel, getter_AddRefs(partURI));
+    rv = aChannel->GetURI(getter_AddRefs (partURI));
     if (NS_FAILED(rv)) return rv;
+//    rv = BuildURI(aChannel, getter_AddRefs(partURI));
+//    if (NS_FAILED(rv)) return rv;
 
     if (mContentType.IsEmpty())
         mContentType = UNKNOWN_CONTENT_TYPE;
@@ -362,6 +364,11 @@ nsMultiMixedConv::SendStart(nsIChannel *aChannel) {
                                                  mContentLength);
     if (NS_FAILED(rv)) return rv;
 
+    nsLoadFlags loadFlags = 0;
+    mPartChannel -> GetLoadAttributes (&loadFlags);
+    loadFlags |= nsIChannel::LOAD_REPLACE;
+    mPartChannel -> SetLoadAttributes ( loadFlags);
+
 	nsCOMPtr<nsILoadGroup> loadGroup;
     (void)aChannel->GetLoadGroup(getter_AddRefs(loadGroup));
     // Add the new channel to the load group (if any)

webshell/src/nsWebShell.cpp

@@ -1352,8 +1352,11 @@ nsWebShell::OnStartURLLoad(nsIDocumentLoader* loader,
 
   // Stop loading of the earlier document completely when the document url
   // load starts.  Now we know that this url is valid and available.
+  nsLoadFlags loadFlags = 0;
+  channel -> GetLoadAttributes (&loadFlags);
+
   PRBool equals = PR_FALSE;
-  if (NS_SUCCEEDED(aURL->Equals(mCurrentURI, &equals)) && equals)
+  if (NS_SUCCEEDED(aURL->Equals(mCurrentURI, &equals)) && equals && !(loadFlags & nsIChannel::LOAD_REPLACE))
     Stop();
 
   /*