Assume all providers may give zero suggest responses.

components/omnibox/keyword_provider.cc

Index: components/omnibox/keyword_provider.cc
diff --git a/components/omnibox/keyword_provider.cc b/components/omnibox/keyword_provider.cc
index d8754e9f14dcf19f9c2d37b7f7349a68c93a5325..5babeccc83c94484981301521075562fe238fac5 100644
--- a/components/omnibox/keyword_provider.cc
+++ b/components/omnibox/keyword_provider.cc
@@ -199,7 +199,8 @@ AutocompleteMatch KeywordProvider::CreateVerbatimMatch(
 }
 
 void KeywordProvider::Start(const AutocompleteInput& input,
-                            bool minimal_changes) {
+                            bool minimal_changes,
+                            bool on_focus) {
   // This object ensures we end keyword mode if we exit the function without
   // toggling keyword mode to on.
   ScopedEndExtensionKeywordMode keyword_mode_toggle(extensions_delegate_.get());
@@ -229,7 +230,7 @@ void KeywordProvider::Start(const AutocompleteInput& input,
   // typed, if the user uses them enough and isn't obviously typing something
   // else.  In this case we'd consider all input here to be query input.
   base::string16 keyword, remaining_input;
-  if (!ExtractKeywordFromInput(input, &keyword, &remaining_input))
+  if (on_focus || !ExtractKeywordFromInput(input, &keyword, &remaining_input))

[Peter Kasting, 2015/01/07 20:16:36]

Nit: I would probably do this in a separate conditional above the comment above,
just because this isn't really related to that comment.

[Maria, 2015/01/08 07:52:38]

Done.

     return;
 
   // Get the best matches for this keyword.