Have resetInternalsObject() handle detached documents.

Source/core/testing/v8/WebCoreTestSupport.cpp

Index: Source/core/testing/v8/WebCoreTestSupport.cpp
diff --git a/Source/core/testing/v8/WebCoreTestSupport.cpp b/Source/core/testing/v8/WebCoreTestSupport.cpp
index 17cac5e093da930486c9883945d80937dcc76a10..b6f41a30319d95fbe33f99549ec950057a22c12e 100644
--- a/Source/core/testing/v8/WebCoreTestSupport.cpp
+++ b/Source/core/testing/v8/WebCoreTestSupport.cpp
@@ -66,7 +66,13 @@ void resetInternalsObject(v8::Local<v8::Context> context)
 
     ScriptState* scriptState = ScriptState::from(context);
     ScriptState::Scope scope(scriptState);
-    Page* page = toDocument(scriptState->executionContext())->frame()->page();
+    Document* document = toDocument(scriptState->executionContext());
+    ASSERT(document);
+    LocalFrame* frame = document->frame();
+    // Should the document have been detached, the page is assumed being destroyed (=> no reset required.)
+    if (!frame)
+        return;
+    Page* page = frame->page();
     ASSERT(page);
     Internals::resetToConsistentState(page);
     InternalSettings::from(*page)->resetToConsistentState();