Add DidNavigateMainFrame to the TabObserver.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/Tab.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/Tab.java b/chrome/android/java/src/org/chromium/chrome/browser/Tab.java
index 1339da20d0c0f46b2ecd2098e2ec64b6e19abfd8..05bc59723762ed414d7bd717c9ccf9499d706c96 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/Tab.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/Tab.java
@@ -302,6 +302,17 @@ public class Tab implements NavigationClient {
         }
 
         @Override
+        public void didNavigateMainFrame(String url, String baseUrl,
+                boolean isNavigationToDifferentPage, boolean isFragmentNavigation, int statusCode) {
+            for (TabObserver observer : mObservers) {
+                observer.onDidNavigateMainFrame(
+                        Tab.this, url, baseUrl, isNavigationToDifferentPage,
+                        isFragmentNavigation, statusCode);
+
+            }
+        }
+
+        @Override
         public void didChangeThemeColor(int color) {
             for (TabObserver observer : mObservers) {
                 observer.onDidChangeThemeColor(color);