[Merge M49][Autofill] Remove warning for CC autofill on secure pages with mixed passive content

components/autofill/core/browser/autofill_manager.cc

Index: components/autofill/core/browser/autofill_manager.cc
diff --git a/components/autofill/core/browser/autofill_manager.cc b/components/autofill/core/browser/autofill_manager.cc
index f13bcc36d88f23dd420c698b2e031ddfb7a5113b..4c346f6ec0a790a3b6b8bb32f2a8492613250d80 100644
--- a/components/autofill/core/browser/autofill_manager.cc
+++ b/components/autofill/core/browser/autofill_manager.cc
@@ -427,9 +427,9 @@ void AutofillManager::OnQueryFormFieldAutofill(int query_id,
           GetProfileSuggestions(*form_structure, field, *autofill_field);
     }
     if (!suggestions.empty()) {
-      // Don't provide credit card suggestions for non-secure pages. However,
-      // do provide a warning to the user. This will generate warnings on pages
-      // with mixed content (which includes forms with an http target).
+      // Don't provide credit card suggestions for non-secure pages, but do
+      // provide them for secure pages with passive mixed content (see impl. of
+      // IsContextSecure).
       if (is_filling_credit_card &&
           !client_->IsContextSecure(form_structure->source_url())) {
         Suggestion warning_suggestion(l10n_util::GetStringUTF16(