[Downloads] Move client guid for AV scanning of downloaded files to chrome/

content/public/browser/download_manager_delegate.cc

Index: content/public/browser/download_manager_delegate.cc
diff --git a/content/public/browser/download_manager_delegate.cc b/content/public/browser/download_manager_delegate.cc
index c33fcd47a5ef0a9bd86221c3f2e3d6a1ffab8676..9351ce227112181992a2f2d9e20d72921e5e4bba 100644
--- a/content/public/browser/download_manager_delegate.cc
+++ b/content/public/browser/download_manager_delegate.cc
@@ -38,6 +38,11 @@ bool DownloadManagerDelegate::GenerateFileHash() {
   return false;
 }
 
+std::string
+DownloadManagerDelegate::ApplicationClientIdForFileScanning() const {
+  return std::string();
+}
+
 DownloadManagerDelegate::~DownloadManagerDelegate() {}
 
 }  // namespace content