Downloads: Added transient flag to download item and download database

content/browser/download/download_item_impl.cc

Index: content/browser/download/download_item_impl.cc
diff --git a/content/browser/download/download_item_impl.cc b/content/browser/download/download_item_impl.cc
index df4a7f826c08fc167e60b7dcd187729d8389f041..dd5e4644d4624ea42c2b382965022c464196c6cb 100644
--- a/content/browser/download/download_item_impl.cc
+++ b/content/browser/download/download_item_impl.cc
@@ -146,6 +146,7 @@ DownloadItemImpl::DownloadItemImpl(
     DownloadInterruptReason interrupt_reason,
     bool opened,
     const base::Time& last_access_time,
+    bool visible,
     const std::vector<DownloadItem::ReceivedSlice>& received_slices,
     const net::NetLogWithSource& net_log)
     : guid_(base::ToUpperASCII(guid)),
@@ -168,6 +169,7 @@ DownloadItemImpl::DownloadItemImpl(
       delegate_(delegate),
       opened_(opened),
       last_access_time_(last_access_time),
+      visible_(visible),
       current_path_(current_path),
       received_bytes_(received_bytes),
       all_data_saved_(state == COMPLETE),
@@ -778,6 +780,10 @@ base::Time DownloadItemImpl::GetLastAccessTime() const {
   return last_access_time_;
 }
 
+bool DownloadItemImpl::IsVisible() const {
+  return visible_;

[vitaliii, 2017/03/07 07:58:56]

Could you add any comment on when IsVisible is false (or at least explain it
here)?

If I encounter this code, I would be confused. It feels like I should not show
items with IsVisible == false in UI, but I am not sure.

[shaktisahu, 2017/03/08 06:51:30]

Comments are usually found above the method declaration in the interface which
in this case is download_item.h.
Yes, the intent here is that if isVisible=false, we shouldn't show this on the
UI.

[dgn, 2017/03/08 13:12:04]

All right, but there is no context to why this is being added. What would make a
download item invisible? How does it affect the behaviour of the item besides
whether it's shown in the UI? Can you please link a bug in the description?

+}
+
 BrowserContext* DownloadItemImpl::GetBrowserContext() const {
   return delegate_->GetBrowserContext();
 }