Implement {Start,Stop}CapturingKeyStrokes for Instant.

chrome/browser/ui/omnibox/omnibox_view.h

Index: chrome/browser/ui/omnibox/omnibox_view.h
diff --git a/chrome/browser/ui/omnibox/omnibox_view.h b/chrome/browser/ui/omnibox/omnibox_view.h
index 692144f48fc5aeb8585e4c18ccab27b1dd8c29a8..c494012721d6804bdc07e8837bfd33dff49421d5 100644
--- a/chrome/browser/ui/omnibox/omnibox_view.h
+++ b/chrome/browser/ui/omnibox/omnibox_view.h
@@ -152,6 +152,10 @@ class OmniboxView {
   // Sets the focus to the autocomplete view.
   virtual void SetFocus() = 0;
 
+  // Sets the focus to the autocomplete view but doesn't visibly show focus to
+  // the user (i.e. no blinking caret or border highlight).

[Mathieu, 2012/11/28 17:56:10]

nit: On Aura, Windows and Gtk, I have not seen border highlight. I would leave
this out.

[samarth, 2012/11/28 19:42:43]

The highlight only exists on Mac afaik. I'll take this out.

+  virtual void SetInvisibleFocus() = 0;
+
   // Called when the temporary text in the model may have changed.
   // |display_text| is the new text to show; |save_original_selection| is true
   // when there wasn't previously a temporary text and thus we need to save off