Disable delegation to picker controller once it is deleted.

chrome/browser/ui/intents/web_intent_picker.h

Index: chrome/browser/ui/intents/web_intent_picker.h
diff --git a/chrome/browser/ui/intents/web_intent_picker.h b/chrome/browser/ui/intents/web_intent_picker.h
index 38348ca98035af0993bbbf4e994499ebb826cfe9..4369b3569b7114ef089141cbb0acdbe06a13b44c 100644
--- a/chrome/browser/ui/intents/web_intent_picker.h
+++ b/chrome/browser/ui/intents/web_intent_picker.h
@@ -103,6 +103,10 @@ class WebIntentPicker {
   // activities.
   virtual void OnPendingAsyncCompleted() = 0;
 
+  // Called once the delegate gets destroyed/invalid. This should only be
+  // called during a shut down sequence that will tear down the picker, too.
+  virtual void InvalidateDelegate() = 0;
+
   // Called when the inline disposition's web contents have been loaded.
   virtual void OnInlineDispositionWebContentsLoaded(
       content::WebContents* web_contents) {}