Implementation of newly designed sign in related histograms for Android

chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentTabsPromoView.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentTabsPromoView.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentTabsPromoView.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentTabsPromoView.java
index 946b28ac1b4b89ee4364c6b8d45dddc84b964593..8356faa2afa7c9253b0986fd5a3624f193826cf7 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentTabsPromoView.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/RecentTabsPromoView.java
@@ -19,6 +19,7 @@ import org.chromium.chrome.R;
 import org.chromium.chrome.browser.firstrun.AccountFirstRunView;
 import org.chromium.chrome.browser.firstrun.ProfileDataCache;
 import org.chromium.chrome.browser.signin.AccountAdder;
+import org.chromium.chrome.browser.signin.SigninManager;
 import org.chromium.chrome.browser.sync.ui.ConfirmAccountChangeFragment;
 import org.chromium.sync.AndroidSyncSettings.AndroidSyncSettingsObserver;
 
@@ -73,6 +74,11 @@ public class RecentTabsPromoView extends FrameLayout implements AndroidSyncSetti
          * @return A ProfileDataCache to retrieve user account info.
          */
         public ProfileDataCache getProfileDataCache();
+
+        /**
+        * @return the access point of creating this view.
+        */
+        public int getAccessPoint();
     }
 
     /**
@@ -282,7 +288,7 @@ public class RecentTabsPromoView extends FrameLayout implements AndroidSyncSetti
                 assert false : "No forced accounts in SignInPromoView";
             }
         });
-
+        SigninManager.logSigninStartAccessPoint(mModel.getAccessPoint());
         return signInPromoView;
     }
 }