Instant API: tell page whether the browser is capturing key strokes.

chrome/browser/ui/omnibox/omnibox_edit_model.h

Index: chrome/browser/ui/omnibox/omnibox_edit_model.h
diff --git a/chrome/browser/ui/omnibox/omnibox_edit_model.h b/chrome/browser/ui/omnibox/omnibox_edit_model.h
index f8444f67bb086fe528660a87a103a257bdf3e1f8..b8bcd4d2f710fa96feaa938be31b8090bf205da1 100644
--- a/chrome/browser/ui/omnibox/omnibox_edit_model.h
+++ b/chrome/browser/ui/omnibox/omnibox_edit_model.h
@@ -12,6 +12,7 @@
 #include "base/time.h"
 #include "chrome/browser/autocomplete/autocomplete_controller_delegate.h"
 #include "chrome/browser/autocomplete/autocomplete_match.h"
+#include "chrome/common/instant_types.h"
 #include "chrome/common/metrics/proto/omnibox_event.pb.h"
 #include "content/public/common/page_transition_types.h"
 #include "googleurl/src/gurl.h"
@@ -223,6 +224,12 @@ class OmniboxEditModel : public AutocompleteControllerDelegate {
   // - User clicks in the omnibox
   // - Omnibox loses and then regains focus
   // - SetFocus() is explicitly called again

[Peter Kasting, 2012/12/06 06:02:30]

Nit: SetFocus() -> OmniboxView::SetFocus() ?

[samarth, 2012/12/06 16:15:50]

Done.

+  // Note that the last two cases often overlap but can happen independently of
+  // each other and so must both be dealt with individually. (For example, if
+  // you tab into the omnibox, OnSetFocus will be called but not SetFocus.  If
+  // the omnibox has invisible focus and you open a second tab, SetFocus will be
+  // called but not OnSetFocus.)

[Peter Kasting, 2012/12/06 06:02:30]

Rather than write so much here, perhaps we need more detail in the comments on
SetFocus() and OnSetFocus() that we can simply refer to from here, which will
make it clear precisely what triggers each one.  Because just from reading your
comments, I'm not sure how to generalize as a reader and guess when one will be
called versus the other.

+  //
   // Caret visibility is tracked per-tab and updates automatically upon
   // switching tabs.
   void SetCaretVisibility(bool visible);
@@ -407,6 +414,11 @@ class OmniboxEditModel : public AutocompleteControllerDelegate {
                                    AutocompleteMatch* match,
                                    GURL* alternate_nav_url) const;
 
+  // Helper for SetCaretVisibility. |reason| is the reason for change that is
+  // passed down to InstantController when we notify it of focus state changes.
+  void SetCaretVisibilityInternal(bool visible,
+                                  OmniboxFocusChangeReason reason);
+
   scoped_ptr<AutocompleteController> autocomplete_controller_;
 
   OmniboxView* view_;