Expose GetLoggingFileName in ContentBrowserClient.

content/public/browser/content_browser_client.cc

Index: content/public/browser/content_browser_client.cc
diff --git a/content/public/browser/content_browser_client.cc b/content/public/browser/content_browser_client.cc
index 7f00fb51046525198fe4a6d4458f08e508718458..9f3dee437061669b2b2faaaef039f066107e8d41 100644
--- a/content/public/browser/content_browser_client.cc
+++ b/content/public/browser/content_browser_client.cc
@@ -463,4 +463,8 @@ bool ContentBrowserClient::RedirectNonUINonIOBrowserThreadsToTaskScheduler() {
   return false;
 }
 
+base::FilePath ContentBrowserClient::GetLoggingFileName() {
+  return base::FilePath();
+}
+
 }  // namespace content