History: Prevent search box from disappearing when search term is deleted.

chrome/browser/resources/history/history_mobile.css

Index: chrome/browser/resources/history/history_mobile.css
diff --git a/chrome/browser/resources/history/history_mobile.css b/chrome/browser/resources/history/history_mobile.css
index 20e4a7e70cfb83dd1e29498efebb2daa2db92dad..bb67407d2e4006e62fc7b8ab237287b3019f499e 100644
--- a/chrome/browser/resources/history/history_mobile.css
+++ b/chrome/browser/resources/history/history_mobile.css
@@ -81,11 +81,6 @@ html[dir='rtl'] #search-field {
   background-position: right 16px center;
 }
 
-/* Hide the search field if it is empty (!valid) and there are no results. */
-body:not(.has-results) #search-field:not(:valid) {
-  display: none;
-}
-
 .no-results-message {
   margin-bottom: 1em;
   padding-left: 16px;