Add DidNavigateMainFrame to the TabObserver.

chrome/android/java/src/org/chromium/chrome/browser/EmptyTabObserver.java

Index: chrome/android/java/src/org/chromium/chrome/browser/EmptyTabObserver.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/EmptyTabObserver.java b/chrome/android/java/src/org/chromium/chrome/browser/EmptyTabObserver.java
index 552a04e0f561cf7fe45492e94f25a8d9ad1cdc04..6a65a123612103f105bd423375ce8ac642a78610 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/EmptyTabObserver.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/EmptyTabObserver.java
@@ -70,5 +70,9 @@ public class EmptyTabObserver implements TabObserver {
             String url, int transitionType) { }
 
     @Override
+    public void onDidNavigateMainFrame(Tab tab, String url, String baseUrl,
+            boolean isNavigationToDifferentPage, boolean isFragmentNavigation, int statusCode) { }
+
+    @Override
     public void onDidChangeThemeColor(int color) { }
 }