Fix the handling of user gestures for external protocol handler dialogs.

chrome/browser/autocomplete/autocomplete_input.cc

Index: chrome/browser/autocomplete/autocomplete_input.cc
diff --git a/chrome/browser/autocomplete/autocomplete_input.cc b/chrome/browser/autocomplete/autocomplete_input.cc
index ea4285172a6a3c21fd963991f877554d079d22ff..ba5c00a891ff8162aad72dc50698635b5605aee3 100644
--- a/chrome/browser/autocomplete/autocomplete_input.cc
+++ b/chrome/browser/autocomplete/autocomplete_input.cc
@@ -198,6 +198,10 @@ AutocompleteInput::Type AutocompleteInput::Parse(
     // handlable schemes (e.g. "javascript") may be treated as "blocked" by the
     // external protocol handler because we don't want pages to open them, but
     // users still can.
+    // Note that the protocol handler needs to be informed that omnibox input
+    // should always be considered "user gesture-triggered", lest it always
+    // return BLOCK.
+    ExternalProtocolHandler::ScopedUserGesture skip_user_gesture_check;
     ExternalProtocolHandler::BlockState block_state =
         ExternalProtocolHandler::GetBlockState(
             base::UTF16ToUTF8(parsed_scheme));