Add mechanism to auto mount file systems in response to a URL request.

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index 0ee29b650385a8a83dba7333e956f7ac2cc8f97f..245432812e14d30bcbea70ddcc9a066a0193bedf 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -2544,6 +2544,10 @@ void ChromeContentBrowserClient::GetAdditionalAllowedSchemesForFileSystem(
   additional_allowed_schemes->push_back(extensions::kExtensionScheme);
 }
 
+void ChromeContentBrowserClient::GetURLRequestAutoMountHandlers(
+    std::vector<fileapi::URLRequestAutoMountHandler>* handlers) {
+}
+
 void ChromeContentBrowserClient::GetAdditionalFileSystemBackends(
     content::BrowserContext* browser_context,
     const base::FilePath& storage_partition_path,