Implement {Start,Stop}CapturingKeyStrokes for Instant.

chrome/renderer/resources/extensions/searchbox_api.js

Index: chrome/renderer/resources/extensions/searchbox_api.js
diff --git a/chrome/renderer/resources/extensions/searchbox_api.js b/chrome/renderer/resources/extensions/searchbox_api.js
index 7952b3b63aea9a10f810770fc2ce153efe021564..8d3a98a8cc3723ad9e16c08d3c4ba7a359763de5 100644
--- a/chrome/renderer/resources/extensions/searchbox_api.js
+++ b/chrome/renderer/resources/extensions/searchbox_api.js
@@ -40,6 +40,8 @@ if (!chrome.searchBox) {
     native function SetQuery();
     native function SetQueryFromAutocompleteResult();
     native function Show();
+    native function StartCapturingKeyStrokes();
+    native function StopCapturingKeyStrokes();
 
     // Returns the |restrictedText| wrapped in a ShadowDOM.
     function SafeWrap(restrictedText) {
@@ -205,6 +207,12 @@ if (!chrome.searchBox) {
     this.navigateContentWindow = function(destination) {
       return NavigateContentWindow(destination);
     };
+    this.startCapturingKeyStrokes = function() {
+      StartCapturingKeyStrokes();
+    };
+    this.stopCapturingKeyStrokes = function() {
+      StopCapturingKeyStrokes();
+    };
     this.onchange = null;
     this.onsubmit = null;
     this.oncancel = null;