jni_generator: Make all object-returning natives return ScopedJavaLocalRef.

chrome/browser/ui/android/navigation_popup.cc

Index: chrome/browser/ui/android/navigation_popup.cc
diff --git a/chrome/browser/ui/android/navigation_popup.cc b/chrome/browser/ui/android/navigation_popup.cc
index 53129a227e54f5d79cf8685fd85a95ac26cb5769..3ddf087bec212c2db5b04ad57eb3c1ade2bd551c 100644
--- a/chrome/browser/ui/android/navigation_popup.cc
+++ b/chrome/browser/ui/android/navigation_popup.cc
@@ -80,8 +80,8 @@ void NavigationPopup::OnFaviconDataAvailable(
       gfx::ConvertToJavaBitmap(image.ToSkBitmap()).obj());
 }
 
-static jstring GetHistoryUrl(JNIEnv* env, jclass clazz) {
-  return ConvertUTF8ToJavaString(env, chrome::kChromeUIHistoryURL).Release();
+static ScopedJavaLocalRef<jstring> GetHistoryUrl(JNIEnv* env, jclass clazz) {
+  return ConvertUTF8ToJavaString(env, chrome::kChromeUIHistoryURL);
 }
 
 static jlong Init(JNIEnv* env, jobject obj) {