Adds the speech recognition button to the app-list searchbox.

chrome/browser/ui/app_list/start_page_observer.h

Index: chrome/browser/ui/app_list/start_page_observer.h
diff --git a/chrome/browser/ui/app_list/start_page_observer.h b/chrome/browser/ui/app_list/start_page_observer.h
index d705b20544769bb7a6ad63cd56cb0cbd3e3754c8..c766e003c5d1e6508145892dfe4d57b7cdbae622 100644
--- a/chrome/browser/ui/app_list/start_page_observer.h
+++ b/chrome/browser/ui/app_list/start_page_observer.h
@@ -14,6 +14,10 @@ class StartPageObserver {
   // Invoked when a search query happens from the start page.
   virtual void OnSearch(const base::string16& query) = 0;
 
+  // Invoked when the online speech recognition state is changed. |recognizing|
+  // is the new state and true when the speech recognition is running currently.
+  virtual void OnSpeechRecognitionStateChanged(bool recognizing) = 0;
+
  protected:
   virtual ~StartPageObserver() {}
 };