[IOS] Show "Detected language" entry even after selecting a language

The "Detected language" should be available even if the user selects
another language.
Test the initial_source_language to achieve that.

(cherry picked from commit 186d092)

Bug: 1404945
Change-Id: I55fcd49bab0d3fa11114b55d9fd6b67deb7036b3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4135123
Reviewed-by: Anthony Cui <cuianthony@chromium.org>
Reviewed-by: Chris Lu <thegreenfrog@chromium.org>
Commit-Queue: Olivier Robin <olivierrobin@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1089132}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4143039
Auto-Submit: Olivier Robin <olivierrobin@chromium.org>
Commit-Queue: Chris Lu <thegreenfrog@chromium.org>
Cr-Commit-Position: refs/branch-heads/5481@{#157}
Cr-Branched-From: 130f3e4-refs/heads/main@{#1084008}

components/translate/core/browser/translate_infobar_delegate.cc

@@ -123,6 +123,10 @@ std::u16string TranslateInfoBarDelegate::source_language_name() const {
   return language_name_at(ui_delegate_.GetSourceLanguageIndex());
 }
 
+std::u16string TranslateInfoBarDelegate::initial_source_language_name() const {
+  return language_name_at(ui_delegate_.GetInitialSourceLanguageIndex());
+}
+
 std::u16string TranslateInfoBarDelegate::target_language_name() const {
   return language_name_at(ui_delegate_.GetTargetLanguageIndex());
 }

components/translate/core/browser/translate_infobar_delegate.h

@@ -102,6 +102,8 @@ class TranslateInfoBarDelegate : public infobars::InfoBarDelegate {
 
   virtual std::u16string source_language_name() const;
 
+  virtual std::u16string initial_source_language_name() const;
+
   virtual std::u16string unknown_language_name() const;
 
   virtual void UpdateSourceLanguage(const std::string& language_code);

components/translate/core/browser/translate_ui_delegate.h

@@ -61,6 +61,11 @@ class TranslateUIDelegate {
   // Returns the source language index.
   size_t GetSourceLanguageIndex() const { return source_language_index_; }
 
+  // Returns the initial source language index.
+  size_t GetInitialSourceLanguageIndex() const {
+    return initial_source_language_index_;
+  }
+
   // Returns the source language code.
   std::string GetSourceLanguageCode() const;
 

ios/chrome/browser/overlays/public/infobar_modal/translate_infobar_modal_overlay_request_config.h

@@ -27,6 +27,10 @@ class TranslateModalRequestConfig
   translate::TranslateStep current_step() const { return current_step_; }
   // The source language name.
   std::u16string source_language_name() const { return source_language_name_; }
+  // The initial source language name.
+  std::u16string initial_source_language_name() const {
+    return initial_source_language_name_;
+  }
   // A special language name the is used when the source language could not be
   // detected.
   std::u16string unknown_language_name() const {
@@ -62,6 +66,7 @@ class TranslateModalRequestConfig
   // Configuration data extracted from `infobar_`'s translate delegate.
   translate::TranslateStep current_step_;
   std::u16string source_language_name_;
+  std::u16string initial_source_language_name_;
   std::u16string unknown_language_name_;
   std::u16string target_language_name_;
   std::vector<std::u16string> language_names_;

ios/chrome/browser/overlays/public/infobar_modal/translate_infobar_modal_overlay_request_config.mm

@@ -28,6 +28,7 @@
 
   current_step_ = delegate->translate_step();
   source_language_name_ = delegate->source_language_name();
+  initial_source_language_name_ = delegate->initial_source_language_name();
   target_language_name_ = delegate->target_language_name();
   unknown_language_name_ = delegate->unknown_language_name();
   for (size_t i = 0; i < delegate->num_languages(); ++i) {

ios/chrome/browser/ui/overlays/infobar_modal/translate/translate_infobar_modal_overlay_mediator.mm

@@ -80,7 +80,9 @@ - (void)setConsumer:(id<InfobarTranslateModalConsumer>)consumer {
   self.newTargetLanguageIndex = kInvalidLanguageIndex;
   self.sourceLanguageIsUnknown = self.config->unknown_language_name() ==
                                  self.config->source_language_name();
-  self.sourceLanguageIsInitiallyUnknown = self.sourceLanguageIsUnknown;
+  self.sourceLanguageIsInitiallyUnknown =
+      self.config->unknown_language_name() ==
+      self.config->initial_source_language_name();
 
   // The Translate button should be enabled whenever the page is untranslated,
   // which may be before any translation has been triggered or after an error