Bug 1428473 Support X-Content-Type-Options: nosniff when navigating r=ckerschb,dragana,alchen

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Apply Requested Revision

Differential Revision: https://phabricator.services.mozilla.com/D33959

parser/html/nsHtml5StreamParser.cpp

@@ -190,7 +190,8 @@ nsHtml5StreamParser::nsHtml5StreamParser(nsHtml5TreeOpExecutor* aExecutor,
       mFlushTimerMutex("nsHtml5StreamParser mFlushTimerMutex"),
       mFlushTimerArmed(false),
       mFlushTimerEverFired(false),
-      mMode(aMode) {
+      mMode(aMode),
+      mSkipContentSniffing(false) {
   NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
 #ifdef DEBUG
   mAtomTable.SetPermittedLookupEventTarget(mEventTarget);
@@ -631,7 +632,7 @@ nsresult nsHtml5StreamParser::FinalizeSniffing(Span<const uint8_t> aFromSegment,
   }
 
   // meta scan failed.
-  if (mCharsetSource < kCharsetFromMetaPrescan) {
+  if (!mSkipContentSniffing && mCharsetSource < kCharsetFromMetaPrescan) {
     // Check for BOMless UTF-16 with Basic
     // Latin content for compat with IE. See bug 631751.
     SniffBOMlessUTF16BasicLatin(aFromSegment.To(aCountToSniffingLimit));
@@ -662,6 +663,7 @@ nsresult nsHtml5StreamParser::SniffStreamBytes(
     Span<const uint8_t> aFromSegment) {
   NS_ASSERTION(IsParserThread(), "Wrong thread!");
   nsresult rv = NS_OK;
+
   // mEncoding and mCharsetSource potentially have come from channel or higher
   // by now. If we find a BOM, SetupDecodingFromBom() will overwrite them.
   // If we don't find a BOM, the previously set values of mEncoding and
@@ -957,6 +959,13 @@ nsresult nsHtml5StreamParser::OnStartRequest(nsIRequest* aRequest) {
     mObserver->OnStartRequest(aRequest);
   }
   mRequest = aRequest;
+  nsCOMPtr<nsIChannel> myChannel(do_QueryInterface(aRequest));
+  nsCOMPtr<nsILoadInfo> loadInfo = myChannel->LoadInfo();
+  mSkipContentSniffing = loadInfo->GetSkipContentSniffing();
+
+  if (mSkipContentSniffing) {
+    mFeedChardet = false;
+  }
 
   mStreamState = STREAM_BEING_READ;