Omnibox UI Experiments: Add flag to change max autocomplete matches.

chrome/browser/flag_descriptions.h

Index: chrome/browser/flag_descriptions.h
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 0e28065dd02dc01e4841ff413ba09e5918581596..de6c3c0252bc8cb727923c91d5347ed2365190af 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -3358,6 +3358,12 @@ extern const char kOmniboxDisplayTitleForCurrentUrlName[];
 // for current URL.
 extern const char kOmniboxDisplayTitleForCurrentUrlDescription[];
 
+// Name of the Omnibox UI max autocomplete matches flag.
+extern const char kOmniboxUIMaxAutocompleteMatchesName[];
+
+// Description of the Omnibox UI max autocomplete matches flag.
+extern const char kOmniboxUIMaxAutocompleteMatchesDescription[];
+
 // Name of the Omnibox UI vertical margin flag.
 extern const char kOmniboxUIVerticalMarginName[];