[omnibox] Add flag, OmniboxUIExperimentUnboldSuggestionText

This CL adds a feature flag to experiment with unbolding
suggestion text in the omnibox.

Bug: 931332
Change-Id: I7ef5ced1a1e86f46e37e1695c7b3d20558e58b3c
Reviewed-on: https://chromium-review.googlesource.com/c/1475746Reviewed-by: Kevin Bailey <krb@chromium.org>
Commit-Queue: Orin Jaworski <orinj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632742}

chrome/browser/ui/views/omnibox/omnibox_text_view.cc

@@ -99,6 +99,10 @@ void ApplyTextStyleForType(SuggestionAnswer::TextStyle text_style,
     case SuggestionAnswer::TextStyle::BOLD:
       style = {part_color, .baseline = gfx::NORMAL_BASELINE,
                .weight = gfx::Font::Weight::BOLD};
+      if (base::FeatureList::IsEnabled(
+              omnibox::kUIExperimentUnboldSuggestionText)) {
+        style.weight = gfx::Font::Weight::NORMAL;
+      }
       break;
     case SuggestionAnswer::TextStyle::NORMAL:
     case SuggestionAnswer::TextStyle::NORMAL_DIM:
@@ -258,9 +262,12 @@ void OmniboxTextView::ReapplyStyling() {
             : text_length;
     const gfx::Range current_range(text_start, text_end);
 
-    // Calculate style-related data.
-    if (classifications[i].style & ACMatchClassification::MATCH)
-      render_text_->ApplyWeight(gfx::Font::Weight::BOLD, current_range);
+    if (!base::FeatureList::IsEnabled(
+            omnibox::kUIExperimentUnboldSuggestionText)) {
+      // Calculate style-related data.
+      if (classifications[i].style & ACMatchClassification::MATCH)
+        render_text_->ApplyWeight(gfx::Font::Weight::BOLD, current_range);
+    }
 
     OmniboxPart part = OmniboxPart::RESULTS_TEXT_DEFAULT;
     if (classifications[i].style & ACMatchClassification::URL) {

components/omnibox/browser/omnibox_field_trial.cc

@@ -246,6 +246,11 @@ extern const base::Feature kUIExperimentUseGenericSearchEngineIcon{
     "OminboxUIExperimentUseGenericSearchEngineIcon",
     base::FEATURE_DISABLED_BY_DEFAULT};
 
+// Feature used to unbold suggestion text.
+const base::Feature kUIExperimentUnboldSuggestionText{
+    "OmniboxUIExperimentUnboldSuggestionText",
+    base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Feature used to enable speculatively starting a service worker associated
 // with the destination of the default match when the user's input looks like a
 // query.

components/omnibox/browser/omnibox_field_trial.h

@@ -54,6 +54,7 @@ extern const base::Feature kUIExperimentVerticalMargin;
 extern const base::Feature kUIExperimentShowSuffixOnAllSearchSuggestions;
 extern const base::Feature kUIExperimentWhiteBackgroundOnBlur;
 extern const base::Feature kUIExperimentUseGenericSearchEngineIcon;
+extern const base::Feature kUIExperimentUnboldSuggestionText;
 extern const base::Feature kSpeculativeServiceWorkerStartOnQueryInput;
 extern const base::Feature kDocumentProvider;
 extern const base::Feature kDedupeGoogleDriveURLs;