Implement {Start,Stop}CapturingKeyStrokes for Instant.

chrome/browser/ui/browser_instant_controller.cc

Index: chrome/browser/ui/browser_instant_controller.cc
diff --git a/chrome/browser/ui/browser_instant_controller.cc b/chrome/browser/ui/browser_instant_controller.cc
index e8f9dba81dfd1b3bd55a267800a09c737ce6d178..2d086e91f576c0182e0af046cd02df3ff6c704ac 100644
--- a/chrome/browser/ui/browser_instant_controller.cc
+++ b/chrome/browser/ui/browser_instant_controller.cc
@@ -14,6 +14,7 @@
 #include "chrome/browser/ui/browser_tabstrip.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/omnibox/location_bar.h"
+#include "chrome/browser/ui/omnibox/omnibox_view.h"
 #include "chrome/browser/ui/search/search.h"
 #include "chrome/browser/ui/search/search_model.h"
 #include "chrome/browser/ui/search/search_tab_helper.h"
@@ -129,6 +130,13 @@ void BrowserInstantController::InstantPreviewFocused() {
       instant_.GetPreviewContents()->web_contents());
 }
 
+void BrowserInstantController::SetInvisibleFocus() {
+  if (browser_->window()->GetLocationBar()) {

[Peter Kasting, 2012/12/01 03:49:58]

When will the window not have a location bar?  We should never NULL-check things
that can't be NULL.

[samarth, 2012/12/03 06:46:15]

I was just following the pattern in SetSuggestion before.  But if this can never
be NULL, I'll just take out the check here and above.

+    browser_->window()->GetLocationBar()->GetLocationEntry()->
+        SetInvisibleFocus();
+  }
+}
+
 TabContents* BrowserInstantController::GetActiveTabContents() const {
   return browser_->tab_strip_model()->GetActiveTabContents();
 }