Basic implementation of showing password fill dialog on page load

components/autofill/content/renderer/autofill_agent.cc

Index: components/autofill/content/renderer/autofill_agent.cc
diff --git a/components/autofill/content/renderer/autofill_agent.cc b/components/autofill/content/renderer/autofill_agent.cc
index 729cbf60e2317e0c06cb96fdcf5b720886b4652f..7a123b41d8b4b0d19249f75d557d483d084114ec 100644
--- a/components/autofill/content/renderer/autofill_agent.cc
+++ b/components/autofill/content/renderer/autofill_agent.cc
@@ -34,6 +34,7 @@
 #include "components/autofill/core/common/form_data_predictions.h"
 #include "components/autofill/core/common/form_field_data.h"
 #include "components/autofill/core/common/password_form.h"
+#include "components/autofill/core/common/password_form_fill_data.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/service_registry.h"
 #include "content/public/common/ssl_status.h"
@@ -220,6 +221,8 @@ bool AutofillAgent::OnMessageReceived(const IPC::Message& message) {
                         OnFillPasswordSuggestion)
     IPC_MESSAGE_HANDLER(AutofillMsg_PreviewPasswordSuggestion,
                         OnPreviewPasswordSuggestion)
+    IPC_MESSAGE_HANDLER(AutofillMsg_ShowInitialPasswordAccountSuggestions,
+                        OnShowInitialPasswordAccountSuggestions);
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -595,6 +598,19 @@ void AutofillAgent::OnPreviewPasswordSuggestion(
   DCHECK(handled);
 }
 
+void AutofillAgent::OnShowInitialPasswordAccountSuggestions(
+    int key,
+    const PasswordFormFillData& form_data) {
+  std::vector<blink::WebInputElement> elements;
+  password_autofill_agent_->GetFillableElementFromFormData(key, form_data,
+                                                           false, &elements);
+  ShowSuggestionsOptions options;
+  options.autofill_on_empty_values = true;
+  options.show_full_suggestion_list = true;
+  for (auto element : elements)
+    ShowSuggestions(element, options);
+}
+
 void AutofillAgent::OnSamePageNavigationCompleted() {
   if (!last_interacted_form_.isNull()) {
     // Assume form submission only if the form is now gone, either invisible or