e10s http: Document channels' cache descriptor causes hang on reloads r=honza

--HG--
branch : GECKO20b5pre_20100820_RELBRANCH

netwerk/protocol/http/HttpChannelChild.cpp

@@ -428,6 +428,7 @@ HttpChannelChild::OnStopRequest(const nsresult& statusCode)
     // We need to keep the document loading channel alive for further 
     // communication, mainly for collecting a security state values.
     mKeptAlive = true;
+    SendDocumentChannelCleanup();
   }
 }
 

netwerk/protocol/http/HttpChannelParent.cpp

@@ -259,6 +259,16 @@ HttpChannelParent::RecvRedirect2Result(const nsresult& result,
   return true;
 }
 
+bool
+HttpChannelParent::RecvDocumentChannelCleanup()
+{
+  // We must clear the cache entry here, else we'll block other channels from
+  // reading it if we've got it open for writing.  
+  mCacheDescriptor = 0;
+
+  return true;
+}
+
 //-----------------------------------------------------------------------------
 // nsIRequestObserver and nsIStreamListener methods equivalents
 //-----------------------------------------------------------------------------

netwerk/protocol/http/HttpChannelParent.h

@@ -109,6 +109,7 @@ protected:
                                                    const PRInt32& low,
                                                    const PRInt32& broken,
                                                    const PRInt32& no);
+  virtual bool RecvDocumentChannelCleanup();
 
   virtual void ActorDestroy(ActorDestroyReason why);
 

netwerk/protocol/http/PHttpChannel.ipdl

@@ -94,6 +94,11 @@ parent:
   // Reports approval/veto of redirect by child process redirect observers
   Redirect2Result(nsresult result, RequestHeaderTuples changedHeaders);
 
+  // For document loads we keep this protocol open after child's
+  // OnStopRequest, and send this msg (instead of __delete__) to allow
+  // partial cleanup on parent. 
+  DocumentChannelCleanup();
+
 child:
   OnStartRequest(nsHttpResponseHead responseHead,
                  PRBool             useResponseHead,