Implement {Start,Stop}CapturingKeyStrokes for Instant.

chrome/browser/instant/instant_controller.h

Index: chrome/browser/instant/instant_controller.h
diff --git a/chrome/browser/instant/instant_controller.h b/chrome/browser/instant/instant_controller.h
index 7c9f11c834bf9191966b2bb3bd1ce88cf990caac..b8ae9d7457cfe870e76617028f1961f837f25e1a 100644
--- a/chrome/browser/instant/instant_controller.h
+++ b/chrome/browser/instant/instant_controller.h
@@ -166,6 +166,14 @@ class InstantController {
   // supports the Instant API.
   void InstantSupportDetermined(InstantLoader* loader, bool supports_instant);
 
+  // Invoked by InstantLoader to notify that the Instant page searchbox lost
+  // focus.
+  void OnWebSearchBoxBlur(InstantLoader* loader);
+
+  // Invoked by InstantLoader to notify that the Instant page searchbox received
+  // focus.
+  void OnWebSearchBoxFocus(InstantLoader* loader);
+
   // Invoked by InstantLoader when it has swapped a different TabContents into
   // the preview, usually because a prerendered page was navigated to.
   void SwappedTabContents(InstantLoader* loader);