[Search] No longer reverting omnibox text on instant search

chrome/browser/ui/omnibox/omnibox_edit_model.cc

Index: chrome/browser/ui/omnibox/omnibox_edit_model.cc
diff --git a/chrome/browser/ui/omnibox/omnibox_edit_model.cc b/chrome/browser/ui/omnibox/omnibox_edit_model.cc
index 507cf65f7607a73e37b5aaf18539d81a6ec9ac27..4dff69e6258f21a1682bdd341b0152b180d78f32 100644
--- a/chrome/browser/ui/omnibox/omnibox_edit_model.cc
+++ b/chrome/browser/ui/omnibox/omnibox_edit_model.cc
@@ -629,7 +629,17 @@ void OmniboxEditModel::OpenMatch(const AutocompleteMatch& match,
         TemplateURLPrepopulateData::kMaxPrepopulatedEngineID);
   }
 
-  if (disposition != NEW_BACKGROUND_TAB) {
+  // Text in the omnibox needs to be reverted in the following cases:
+  // (1) Non-instant-extended query is committed (except to a background tab,
+  //     where the query stays in the omnibox e.g. middle-click).
+  // (2) Instant-extended query is committed on a new tab (foreground or
+  //     background). Current tab should show previous, reverted query.
+  bool is_instant_extended_search = controller()->GetInstant() &&
+      controller()->GetInstant()->IsInstantExtendedSearch();
+  if ((disposition != NEW_BACKGROUND_TAB && !is_instant_extended_search) ||
+      (is_instant_extended_search &&
+          (disposition == NEW_BACKGROUND_TAB ||
+           disposition == NEW_FOREGROUND_TAB))) {
     base::AutoReset<bool> tmp(&in_revert_, true);
     view_->RevertAll();  // Revert the box to its unedited state
   }