Simplify use of unique_renderer_ids

The creation of the map was completely redundant, so I have removed it.

Bug: 896173
Change-Id: Ibe28940c458de4f18b28d958e0d4d34581bbdf77
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2279825
Commit-Queue: Dominic Battré <battre@chromium.org>
Auto-Submit: Dominic Battré <battre@chromium.org>
Reviewed-by: Matthias Körber <koerber@google.com>
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#788576}

chrome/browser/autofill/form_structure_browsertest.cc

@@ -93,16 +93,11 @@ std::vector<base::FilePath> GetTestFiles() {
 
 std::string FormStructuresToString(
     const std::map<FormRendererId, std::unique_ptr<FormStructure>>& forms) {
-  std::map<uint32_t, const FormStructure*> sorted_forms;
-  for (const auto& form_kv : forms) {
-    const auto* form = form_kv.second.get();
-    uint32_t renderer_id = form->unique_renderer_id().value();
-    EXPECT_TRUE(sorted_forms.emplace(renderer_id, form).second);
-  }
-
   std::string forms_string;
-  for (const auto& kv : sorted_forms) {
-    const auto* form = kv.second;
+  // The forms are sorted by renderer ID, which should make the order
+  // deterministic.
+  for (const auto& kv : forms) {
+    const auto* form = kv.second.get();
     for (const auto& field : *form) {
       forms_string += field->Type().ToString();
       forms_string += " | " + base::UTF16ToUTF8(field->name);

ios/chrome/browser/autofill/form_structure_browsertest.mm

@@ -206,16 +206,11 @@ void FormStructureBrowserTest::GenerateResults(const std::string& input,
 
 std::string FormStructureBrowserTest::FormStructuresToString(
     const std::map<FormRendererId, std::unique_ptr<FormStructure>>& forms) {
-  std::map<uint32_t, const FormStructure*> sorted_forms;
+  std::string forms_string;
+  // The forms are sorted by renderer ID, which should make the order
+  // deterministic.
   for (const auto& form_kv : forms) {
     const auto* form = form_kv.second.get();
-    uint32_t renderer_id = form->unique_renderer_id().value();
-    EXPECT_TRUE(sorted_forms.emplace(renderer_id, form).second);
-  }
-
-  std::string forms_string;
-  for (const auto& form_kv : sorted_forms) {
-    const auto* form = form_kv.second;
     for (const auto& field : *form) {
       std::string name = base::UTF16ToUTF8(field->name);
       if (base::StartsWith(name, "gChrome~field~",