Linux: support append to password list in the GNOME keyring backend to fix initial password sync.

chrome/browser/password_manager/native_backend_gnome_x.cc

Index: chrome/browser/password_manager/native_backend_gnome_x.cc
===================================================================
--- chrome/browser/password_manager/native_backend_gnome_x.cc	(revision 97665)
+++ chrome/browser/password_manager/native_backend_gnome_x.cc	(working copy)
@@ -382,7 +382,14 @@
 GnomeKeyringResult GKRMethod::WaitResult(PasswordFormList* forms) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
   event_.Wait();
-  forms->swap(forms_);
+  if (forms->empty()) {
+    // Normal case. Avoid extra allocation by swapping.
+    forms->swap(forms_);

[Evan Martin, 2011/08/23 14:36:07]

Is this performance critical?  I wonder if it's worth the extra code.  It seems
this is a vector of pointers, so either way the total amount of data being moved
around is on the order of 200 bytes.

[Mike Mammarella, 2011/08/23 19:40:20]

No, it's not performance critical. It would probably be fine to just do the copy
always. On the other hand it's really not much code and it "feels" better to me
to avoid the unnecessary copy since it's so easy to do. If you want I'll remove
it but otherwise I'm inclined to leave it.

+  } else {
+    // Rare case. Append forms_ to *forms.
+    forms->insert(forms->end(), forms_.begin(), forms_.end());
+    forms_.clear();
+  }
   return result_;
 }