Allow the external protocol dialog to handle FORM_SUBMIT navigation

chrome/browser/chromeos/arc/arc_external_protocol_dialog.cc

Index: chrome/browser/chromeos/arc/arc_external_protocol_dialog.cc
diff --git a/chrome/browser/chromeos/arc/arc_external_protocol_dialog.cc b/chrome/browser/chromeos/arc/arc_external_protocol_dialog.cc
index 59a5c1b0a39c09a7e76831874522c2437076714e..915ea48da71f8cd3998d657781fe0193ec0e8462 100644
--- a/chrome/browser/chromeos/arc/arc_external_protocol_dialog.cc
+++ b/chrome/browser/chromeos/arc/arc_external_protocol_dialog.cc
@@ -166,7 +166,9 @@ bool RunArcExternalProtocolDialog(const GURL& url,
                                   int routing_id,
                                   ui::PageTransition page_transition,
                                   bool has_user_gesture) {
-  if (ShouldIgnoreNavigation(page_transition))
+  // Try to forward <form> submissions to ARC when possible.
+  constexpr bool kAllowFormSubmit = true;
+  if (ShouldIgnoreNavigation(page_transition, kAllowFormSubmit))
     return false;
 
   mojom::IntentHelperInstance* intent_helper = GetIntentHelper();