Bug 1520812. Remove bogus assertion in nsExpatDriver::HandleError. r=hsivonen

Any time we stop a load of an XML document before we've gotten all the data,
we'll end up in this code with mSink null, because nsParser::Terminate ends up
calling nsExpatDriver::DidBuildModel which nulls out mSink, and not getting all
the data means the XML won't be well-formed.

Differential Revision: https://phabricator.services.mozilla.com/D16856

--HG--
extra : moz-landing-system : lando

parser/htmlparser/nsExpatDriver.cpp

@@ -732,8 +732,6 @@ nsresult nsExpatDriver::HandleError() {
   CreateErrorText(description.get(), XML_GetBase(mExpatParser), lineNumber,
                   colNumber, errorText);
 
-  NS_ASSERTION(mSink, "no sink?");
-
   nsAutoString sourceText(mLastLine);
   AppendErrorPointer(colNumber, mLastLine.get(), sourceText);
 
@@ -749,6 +747,7 @@ nsresult nsExpatDriver::HandleError() {
   // If it didn't initialize, we can't do any logging.
   bool shouldReportError = NS_SUCCEEDED(rv);
 
+  // mSink might be null here if our parser was terminated.
   if (mSink && shouldReportError) {
     rv = mSink->ReportError(errorText.get(), sourceText.get(), serr,
                             &shouldReportError);
@@ -757,6 +756,7 @@ nsresult nsExpatDriver::HandleError() {
     }
   }
 
+  // mOriginalSink might be null here if our parser was terminated.
   if (mOriginalSink) {
     nsCOMPtr<Document> doc = do_QueryInterface(mOriginalSink->GetTarget());
     if (doc && doc->SuppressParserErrorConsoleMessages()) {

testing/web-platform/meta/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/bailout-exception-vs-return-xml.window.js.ini

@@ -1,2 +0,0 @@
-[bailout-exception-vs-return-xml.window.html]
-  max-asserts: 2