Return early from TextAutosizer::updatePageInfo for remote main frame.

Source/core/rendering/TextAutosizer.cpp

Index: Source/core/rendering/TextAutosizer.cpp
diff --git a/Source/core/rendering/TextAutosizer.cpp b/Source/core/rendering/TextAutosizer.cpp
index 226c2894214abbd795d09dd63e2337002984b9a1..28c18dd72dd83dc0719e6e765196f59196d8b32d 100644
--- a/Source/core/rendering/TextAutosizer.cpp
+++ b/Source/core/rendering/TextAutosizer.cpp
@@ -509,6 +509,12 @@ void TextAutosizer::updatePageInfo()
         RenderView* renderView = m_document->renderView();
         bool horizontalWritingMode = isHorizontalWritingMode(renderView->style()->writingMode());
 
+        // FIXME: With out-of-process iframes, the top frame can be remote and
+        // doesn't have sizing information. Just return if this is the case.
+        Frame* frame = m_document->frame()->tree().top();
+        if (frame->isRemoteFrame())
+            return;
+
         LocalFrame* mainFrame = m_document->page()->deprecatedLocalMainFrame();
         IntSize frameSize = m_document->settings()->textAutosizingWindowSizeOverride();
         if (frameSize.isEmpty())