[omnibox] Add about:flags entry for OmniboxSuggestionButtonRow feature

This CL creates and registers metadata for a new flag called
omnibox-suggestion-button-row.

Bug: 1046523
Change-Id: I96068d55562147a11f1fcf1524d4bb373a204875
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2026712
Commit-Queue: Orin Jaworski <[email protected]>
Reviewed-by: Tommy Li <[email protected]>
Cr-Commit-Position: refs/heads/master@{#736517}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 5ea99f7..8cbd171 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -2807,6 +2807,11 @@
     "Enable omnibox Pedal suggestions to accelerate actions within Chrome by "
     "detecting user intent and offering direct access to the end goal.";
 
+const char kOmniboxSuggestionButtonRowName[] = "Omnibox suggestion button row";
+const char kOmniboxSuggestionButtonRowDescription[] =
+    "Enable a button row on omnibox suggestions to present actionable items "
+    "such as keyword search, tab-switch buttons, and Pedals.";
+
 const char kOmniboxReverseAnswersName[] = "Omnibox reverse answers";
 const char kOmniboxReverseAnswersDescription[] =
     "Display answers with rows reversed (swapped); except definitions.";