TextAutosizer should handle cross-process navigation and RemoteFrame.

third_party/WebKit/Source/core/layout/TextAutosizer.cpp

Index: third_party/WebKit/Source/core/layout/TextAutosizer.cpp
diff --git a/third_party/WebKit/Source/core/layout/TextAutosizer.cpp b/third_party/WebKit/Source/core/layout/TextAutosizer.cpp
index 4d2bed9ce3ec90a091fb87dbea191f68847b853b..bba079508dbc56c33b354a81a87448f485c90fe8 100644
--- a/third_party/WebKit/Source/core/layout/TextAutosizer.cpp
+++ b/third_party/WebKit/Source/core/layout/TextAutosizer.cpp
@@ -531,10 +531,7 @@ void TextAutosizer::updatePageInfo()
         if (frame->isRemoteFrame())
             return;
 
-        LocalFrame* mainFrame = m_document->page()->deprecatedLocalMainFrame();
-        if (!mainFrame->view())
-            return;
-
+        LocalFrame* mainFrame = toLocalFrame(frame);
         IntSize frameSize = m_document->settings()->textAutosizingWindowSizeOverride();
         if (frameSize.isEmpty())
             frameSize = windowSize();