Bug 534478, prevent assertions caused by reftest pagemode, r=dbaron

--HG--
extra : rebase_source : c2bec911560c952009783a83a93ced887447937d

layout/base/nsDocumentViewer.cpp

@@ -943,12 +943,15 @@ DocumentViewerImpl::InitInternal(nsIWidget* aParentWidget,
                               getter_AddRefs(window));
 
       if (window) {
+        nsCOMPtr<nsIDocument> curDoc =
+          do_QueryInterface(window->GetExtantDocument());
+        if (!mIsPageMode || curDoc != mDocument) {
           window->SetNewDocument(mDocument, aState);
-
           nsJSContext::LoadStart();
         }
       }
     }
+  }
 
   if (aDoCreation && mPresContext) {
     // The ViewManager and Root View was created above (in
@@ -2368,7 +2371,7 @@ DocumentViewerImpl::FindContainerView()
 nsresult
 DocumentViewerImpl::CreateDeviceContext(nsIView* aContainerView)
 {
-  NS_PRECONDITION(!mPresShell && !mPresContext && !mWindow,
+  NS_PRECONDITION(!mPresShell && !mWindow,
                   "This will screw up our existing presentation");
   NS_PRECONDITION(mDocument, "Gotta have a document here");
   

layout/tools/reftest/reftest.js

@@ -744,13 +744,9 @@ function OnDocumentLoad(event)
        ps.footerStrRight = "";
        gBrowser.docShell.contentViewer.setPageMode(true, ps);
 
-       // WORKAROUND FOR ASSERTIONS IN BUG 534478:  Calling setPageMode
-       // above causes 2 assertions.  So that we don't have to annotate
-       // the manifests for every reftest-print reftest, bump the
-       // assertion count by two right here.
-       // And on Mac, it causes *three* assertions.
+       // WORKAROUND FOR AN ASSERTION ON MAC!
        var xr = CC[NS_XREAPPINFO_CONTRACTID].getService(CI.nsIXULRuntime);
-       var count = (xr.widgetToolkit == "cocoa") ? 3 : 2;
+       var count = (xr.widgetToolkit == "cocoa") ? 1 : 0;
        gURLs[0].minAsserts += count;
        gURLs[0].maxAsserts += count;
     }