Download shelf autohides on showing in shell, just same as regular open

chrome/browser/platform_util_mac.mm

Index: chrome/browser/platform_util_mac.mm
diff --git a/chrome/browser/platform_util_mac.mm b/chrome/browser/platform_util_mac.mm
index cb0c3096ddb7cad41bf734498f21136748322875..44196b00a9bb751f2fe19f24c4c6e74878309212 100644
--- a/chrome/browser/platform_util_mac.mm
+++ b/chrome/browser/platform_util_mac.mm
@@ -19,7 +19,10 @@
 
 namespace platform_util {
 
-void ShowItemInFolder(Profile* profile, const base::FilePath& full_path) {
+namespace internal {
+
+void PlatformShowItemInFolder(Profile* profile,
+                              const base::FilePath& full_path) {
   DCHECK([NSThread isMainThread]);
   NSString* path_string = base::SysUTF8ToNSString(full_path.value());
   if (!path_string || ![[NSWorkspace sharedWorkspace] selectFile:path_string
@@ -27,6 +30,8 @@ void ShowItemInFolder(Profile* profile, const base::FilePath& full_path) {
     LOG(WARNING) << "NSWorkspace failed to select file " << full_path.value();
 }
 
+} // namespace internal
+
 void OpenFileOnMainThread(const base::FilePath& full_path) {
   DCHECK([NSThread isMainThread]);
   NSString* path_string = base::SysUTF8ToNSString(full_path.value());