Fix crash in FontFaceSet::ready

third_party/WebKit/Source/core/css/FontFaceSet.cpp

Index: third_party/WebKit/Source/core/css/FontFaceSet.cpp
diff --git a/third_party/WebKit/Source/core/css/FontFaceSet.cpp b/third_party/WebKit/Source/core/css/FontFaceSet.cpp
index 00ecea4a70fc5d2108111c84756b1ae9c97a904c..46edb57de7f6c781cf715999782a5a0f969e92c7 100644
--- a/third_party/WebKit/Source/core/css/FontFaceSet.cpp
+++ b/third_party/WebKit/Source/core/css/FontFaceSet.cpp
@@ -243,7 +243,8 @@ void FontFaceSet::removeFromLoadingFonts(FontFace* fontFace) {
 }
 
 ScriptPromise FontFaceSet::ready(ScriptState* scriptState) {
-  if (m_ready->getState() != ReadyProperty::Pending) {
+  if (m_ready->getState() != ReadyProperty::Pending &&
+      inActiveDocumentContext()) {
     // |m_ready| is already resolved, but there may be pending stylesheet
     // changes and/or layout operations that may cause another font loads.
     // So synchronously update style and layout here.