Ensure RemoteFontFaceSource doesn't try to start a load in a detached document

third_party/WebKit/Source/platform/testing/weburl_loader_mock.cc

Index: third_party/WebKit/Source/platform/testing/weburl_loader_mock.cc
diff --git a/third_party/WebKit/Source/platform/testing/weburl_loader_mock.cc b/third_party/WebKit/Source/platform/testing/weburl_loader_mock.cc
index bf961a08663ce53671e6719f75c22ac868fade2c..0da20c153c3e6af14c8db42afb00d94ff6cd1f67 100644
--- a/third_party/WebKit/Source/platform/testing/weburl_loader_mock.cc
+++ b/third_party/WebKit/Source/platform/testing/weburl_loader_mock.cc
@@ -154,9 +154,10 @@ void WebURLLoaderMock::setDefersLoading(bool deferred) {
   NOTIMPLEMENTED();
 }
 
-void WebURLLoaderMock::setLoadingTaskRunner(WebTaskRunner*) {
+void WebURLLoaderMock::setLoadingTaskRunner(WebTaskRunner* runner) {
   // In principle this is NOTIMPLEMENTED(), but if we put that here it floods
   // the console during webkit unit tests, so we leave the function empty.
+  DCHECK(runner);
 }
 
 WeakPtr<WebURLLoaderMock> WebURLLoaderMock::GetWeakPtr() {