Suppress spurious console errors for XHR response codes 201, 202, 204, 205 and 304.

Parse errors for XML data are already handled in 4d8f9a9add1805a5cb3b7fd1cc1ff8dd4b020fe4  -- this is a follow-up to suppress unnecessary console errors.

dom/base/nsIDocument.h

@@ -237,6 +237,9 @@ public:
   virtual void SetSuppressParserErrorElement(bool aSuppress) {}
   virtual bool SuppressParserErrorElement() { return false; }
 
+  virtual void SetSuppressParserErrorConsoleMessages(bool aSuppress) {}
+  virtual bool SuppressParserErrorConsoleMessages() { return false; }
+
   /**
    * Signal that the document title may have changed
    * (see nsDocument::GetTitle).

dom/base/nsXMLHttpRequest.cpp

@@ -2158,6 +2158,16 @@ nsXMLHttpRequest::OnStartRequest(nsIRequest *request, nsISupports *ctxt)
     mResponseXML->SetChromeXHRDocURI(chromeXHRDocURI);
     mResponseXML->SetChromeXHRDocBaseURI(chromeXHRDocBaseURI);
 
+    // suppress parsing failure messages to console for statuses which
+    // can have empty bodies (see bugs 884693 + 1329365).
+    uint32_t responseStatus;
+    if (NS_SUCCEEDED(GetStatus(&responseStatus)) &&
+        (responseStatus == 201 || responseStatus == 202 ||
+         responseStatus == 204 || responseStatus == 205 ||
+         responseStatus == 304)) {
+      mResponseXML->SetSuppressParserErrorConsoleMessages(true);
+    }
+
     if (nsContentUtils::IsSystemPrincipal(mPrincipal)) {
       mResponseXML->ForceEnableXULXBL();
     }

dom/xml/XMLDocument.cpp

@@ -524,6 +524,18 @@ XMLDocument::SuppressParserErrorElement()
   return mSuppressParserErrorElement;
 }
 
+void
+XMLDocument::SetSuppressParserErrorConsoleMessages(bool aSuppress)
+{
+  mSuppressParserErrorConsoleMessages = aSuppress;
+}
+
+bool
+XMLDocument::SuppressParserErrorConsoleMessages()
+{
+  return mSuppressParserErrorConsoleMessages;
+}
+
 nsresult
 XMLDocument::StartDocumentLoad(const char* aCommand,
                                nsIChannel* aChannel,

dom/xml/XMLDocument.h

@@ -33,6 +33,9 @@ public:
   virtual void SetSuppressParserErrorElement(bool aSuppress) override;
   virtual bool SuppressParserErrorElement() override;
 
+  virtual void SetSuppressParserErrorConsoleMessages(bool aSuppress) override;
+  virtual bool SuppressParserErrorConsoleMessages() override;
+
   virtual nsresult StartDocumentLoad(const char* aCommand, nsIChannel* channel,
                                      nsILoadGroup* aLoadGroup,
                                      nsISupports* aContainer,
@@ -93,6 +96,9 @@ protected:
   // If true, do not output <parsererror> elements. Per spec, XMLHttpRequest
   // shouldn't output them, whereas DOMParser/others should (see bug 918703).
   bool mSuppressParserErrorElement;
+
+  // If true, do not log parsing errors to the web console (see bug 884693).
+  bool mSuppressParserErrorConsoleMessages;
 };
 
 } // namespace dom

parser/htmlparser/nsExpatDriver.cpp

@@ -988,6 +988,11 @@ nsExpatDriver::HandleError()
     }
   }
 
+  nsCOMPtr<nsIDocument> doc = do_QueryInterface(mOriginalSink->GetTarget());
+  if (doc && doc->SuppressParserErrorConsoleMessages()) {
+    shouldReportError = false;
+  }
+
   if (shouldReportError) {
     nsCOMPtr<nsIConsoleService> cs
       (do_GetService(NS_CONSOLESERVICE_CONTRACTID));