Fix font preload crash

third_party/WebKit/Source/core/loader/DocumentLoader.cpp

Index: third_party/WebKit/Source/core/loader/DocumentLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
index e9498218cf2fbbd83ea56c8714a1b73c3f1ba69c..80bca0bc223ff9bb0e45494c21ea7d7f22c7b4fe 100644
--- a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
@@ -180,7 +180,8 @@ Resource* DocumentLoader::startPreload(Resource::Type type, FetchRequest& reques
     case Resource::Font:
         resource = FontResource::fetch(request, fetcher());
         // This is needed for fonts as loading doesn't start until there's usage.
-        toFontResource(resource)->beginLoadIfNeeded(fetcher());
+        if (resource)
+            toFontResource(resource)->beginLoadIfNeeded(fetcher());
         break;
     case Resource::Media:
         resource = RawResource::fetchMedia(request, fetcher());