Replicate to all renderers the accepted languages set by a layout test.

components/test_runner/test_runner.cc

Index: components/test_runner/test_runner.cc
diff --git a/components/test_runner/test_runner.cc b/components/test_runner/test_runner.cc
index 903f6360b96061964cbc1ec321ed7f5c597f91f3..d7a927a3781cbbbc9af34be513ee77a42231fabb 100644
--- a/components/test_runner/test_runner.cc
+++ b/components/test_runner/test_runner.cc
@@ -2656,8 +2656,17 @@ void TestRunner::OverridePreference(const std::string& key,
   delegate_->ApplyPreferences();
 }
 
+std::string TestRunner::GetAcceptLanguages() const {
+  return layout_test_runtime_flags_.accept_languages();
+}
+
 void TestRunner::SetAcceptLanguages(const std::string& accept_languages) {
-  proxy_->SetAcceptLanguages(accept_languages);
+  if (accept_languages == GetAcceptLanguages())
+    return;
+
+  layout_test_runtime_flags_.set_accept_languages(accept_languages);
+  OnLayoutTestRuntimeFlagsChanged();
+  proxy_->GetWebView()->acceptLanguagesChanged();
 }
 
 void TestRunner::SetPluginsEnabled(bool enabled) {