Suppress Autofill popup if it would be outside the viewport.

chrome/browser/ui/autofill/chrome_autofill_client.cc

Index: chrome/browser/ui/autofill/chrome_autofill_client.cc
diff --git a/chrome/browser/ui/autofill/chrome_autofill_client.cc b/chrome/browser/ui/autofill/chrome_autofill_client.cc
index 6b85038c7ef3f6ec306378270330550825c2d9fc..94be3118640adbf26ec7c7341d92d36fb004844f 100644
--- a/chrome/browser/ui/autofill/chrome_autofill_client.cc
+++ b/chrome/browser/ui/autofill/chrome_autofill_client.cc
@@ -256,6 +256,15 @@ void ChromeAutofillClient::ShowAutofillPopup(
   gfx::RectF element_bounds_in_screen_space =
       element_bounds + client_area.OffsetFromOrigin();
 
+  if (element_bounds.IsEmpty() ||
+      !gfx::RectF(client_area).Contains(element_bounds_in_screen_space)) {
+    // The field associated with the popup:
+    // - takes up zero space (and is possibly not in the DOM), or
+    // - is partially or fully outside the viewport,
+    // so we suppress the popup to avoid crbug.com/678713
+    return;
+  }
+
   // Will delete or reuse the old |popup_controller_|.
   popup_controller_ =
       AutofillPopupControllerImpl::GetOrCreate(popup_controller_,