[Extensions UI] Handle multiple warning bubbles racing to show

chrome/browser/ui/extensions/settings_api_bubble_helpers.cc

Index: chrome/browser/ui/extensions/settings_api_bubble_helpers.cc
diff --git a/chrome/browser/ui/extensions/settings_api_bubble_helpers.cc b/chrome/browser/ui/extensions/settings_api_bubble_helpers.cc
index c757590e0ec243d0564ffe5b42da094732b3a04f..9bdb1a6ed314c40283374a37597e4f7fcf592dfc 100644
--- a/chrome/browser/ui/extensions/settings_api_bubble_helpers.cc
+++ b/chrome/browser/ui/extensions/settings_api_bubble_helpers.cc
@@ -27,12 +27,17 @@ namespace {
 
 void ShowSettingsApiBubble(SettingsApiOverrideType type,
                            Browser* browser) {
+  ToolbarActionsModel* model = ToolbarActionsModel::Get(browser->profile());
+  if (model->has_active_bubble())
+    return;
+
   std::unique_ptr<ExtensionMessageBubbleController> settings_api_bubble(
       new ExtensionMessageBubbleController(
           new SettingsApiBubbleDelegate(browser->profile(), type), browser));
   if (!settings_api_bubble->ShouldShow())
     return;
 
+  settings_api_bubble->SetIsActiveBubble();

[Finnur, 2016/06/20 10:39:00]

I'm a little worried that we need to do this manually, which might be forgotten
and we don't have a good way to detect it. Don't have a good suggestion though
as to how to solve it.

[Devlin, 2016/06/20 17:58:39]

I agree.  I tried a number of different solutions, and in the end, I think this
was the cleanest, even though I'm not a huge fan.  We really need to rework the
whole bubble system now that we have so many that are showing on multiple
platforms, but this patch isn't really the right place for it.  I'm also pushing
UI to think about these bubbles in general more (because I think they're not
quite getting the right result) so when there's some movement there, it might be
a good time to rethink it more completely.

   ToolbarActionsBar* toolbar_actions_bar =
       browser->window()->GetToolbarActionsBar();
   std::unique_ptr<ToolbarActionsBarBubbleDelegate> bridge(
@@ -89,12 +94,17 @@ void MaybeShowExtensionControlledNewTabPage(
   if (ntp_url != active_url)
     return;  // Not being overridden by an extension.
 
+  ToolbarActionsModel* model = ToolbarActionsModel::Get(browser->profile());
+  if (model->has_active_bubble())
+    return;
+
   std::unique_ptr<ExtensionMessageBubbleController> ntp_overridden_bubble(
       new ExtensionMessageBubbleController(
           new NtpOverriddenBubbleDelegate(browser->profile()), browser));
   if (!ntp_overridden_bubble->ShouldShow())
     return;
 
+  ntp_overridden_bubble->SetIsActiveBubble();
   ToolbarActionsBar* toolbar_actions_bar =
       browser->window()->GetToolbarActionsBar();
   std::unique_ptr<ToolbarActionsBarBubbleDelegate> bridge(