Bug 690990. Don't assert that sheets are not modified when it would be just fine for them to be modified. r=peterv

2011-10-03 15:11:59 -04:00 · 2011-10-03 15:11:59 -04:00 · 11b5bde3e2
--- a/layout/style/Loader.cpp
+++ b/layout/style/Loader.cpp
@ -1744,9 +1744,12 @@ Loader::DoSheetComplete(SheetLoadData* aLoadData, nsresult aStatus,
  // Go through and deal with the whole linked list.
  SheetLoadData* data = aLoadData;
  while (data) {
-    NS_ABORT_IF_FALSE(!data->mSheet->IsModified(),
-                      "should not get marked modified during parsing");
    if (!data->mSheetAlreadyComplete) {
+      // If mSheetAlreadyComplete, then the sheet could well be modified between
+      // when we posted the async call to SheetComplete and now, since the sheet
+      // was page-accessible during that whole time.
+      NS_ABORT_IF_FALSE(!data->mSheet->IsModified(),
+                        "should not get marked modified during parsing");
      data->mSheet->SetComplete();
      data->ScheduleLoadEventIfNeeded(aStatus);
    }
--- a/layout/style/crashtests/690990-1.html
+++ b/layout/style/crashtests/690990-1.html
@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<html class="reftest-wait">
+
+<link id="e" href="data:text/css,.ref { background-color: green; }" rel="stylesheet">
+
+<script>
+
+function boom()
+{
+  document.documentElement.appendChild(document.getElementById("e"));
+  document.styleSheets[0].cssRules[0];
+  // Remove reftest-wait async so we give the SheetComplete a chance to run
+  setTimeout(function() { document.documentElement.className = ""; }, 0);
+}
+
+</script>
+
+<body onload="boom();"></body>
+
+</html>
--- a/layout/style/crashtests/crashtests.list
+++ b/layout/style/crashtests/crashtests.list
@ -72,3 +72,4 @@ load 611922-1.html
 load 665209-1.html
 asserts(2) load 671799-1.html
 asserts(2) load 671799-2.html
+load 690990-1.html