Assume all providers may give zero suggest responses.

chrome/browser/autocomplete/builtin_provider.cc

Index: chrome/browser/autocomplete/builtin_provider.cc
diff --git a/chrome/browser/autocomplete/builtin_provider.cc b/chrome/browser/autocomplete/builtin_provider.cc
index 2bf721e7579709baa906064e286cb2a554a01481..64c21a6bcf66b356ee3e4f06189ef787066b44e9 100644
--- a/chrome/browser/autocomplete/builtin_provider.cc
+++ b/chrome/browser/autocomplete/builtin_provider.cc
@@ -61,9 +61,10 @@ BuiltinProvider::BuiltinProvider()
 }
 
 void BuiltinProvider::Start(const AutocompleteInput& input,
-                            bool minimal_changes) {
+                            bool minimal_changes,
+                            bool on_focus) {
   matches_.clear();
-  if ((input.type() == metrics::OmniboxInputType::INVALID) ||
+  if (on_focus || (input.type() == metrics::OmniboxInputType::INVALID) ||
       (input.type() == metrics::OmniboxInputType::FORCED_QUERY) ||
       (input.type() == metrics::OmniboxInputType::QUERY))
     return;