[Autofill] Add support for signin promo on Android

chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninActivity.java

Index: chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninActivity.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninActivity.java
index 4717325e329ea0b2e7b52bcea9cd4b4f4c9b7243..2e1e357d74bd42739632cfb8905c0798bed78575 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/signin/AccountSigninActivity.java
@@ -41,7 +41,7 @@ public class AccountSigninActivity extends AppCompatActivity
 
     @IntDef({SigninAccessPoint.SETTINGS, SigninAccessPoint.BOOKMARK_MANAGER,
             SigninAccessPoint.RECENT_TABS, SigninAccessPoint.SIGNIN_PROMO,
-            SigninAccessPoint.NTP_LINK})
+            SigninAccessPoint.NTP_LINK, SigninAccessPoint.AUTOFILL_DROPDOWN})
     @Retention(RetentionPolicy.SOURCE)
     public @interface AccessPoint {}
     @AccessPoint private int mAccessPoint;
@@ -51,9 +51,13 @@ public class AccountSigninActivity extends AppCompatActivity
      * intent.
      * @param accessPoint - A SigninAccessPoint designating where the activity is created from.
      */
-    public static void startAccountSigninActivity(Context context, @AccessPoint int accessPoint) {
+    public static void startAccountSigninActivity(
+            Context context, @AccessPoint int accessPoint, boolean useNewTaskFlag) {
         Intent intent = new Intent(context, AccountSigninActivity.class);
         intent.putExtra(INTENT_SIGNIN_ACCESS_POINT, accessPoint);
+        if (useNewTaskFlag) {
+            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+        }
         context.startActivity(intent);
     }
 
@@ -71,7 +75,7 @@ public class AccountSigninActivity extends AppCompatActivity
             return false;
         }
 
-        startAccountSigninActivity(context, accessPoint);
+        startAccountSigninActivity(context, accessPoint, /* useNewTaskFlag */ false);
         return true;
     }
 
@@ -97,7 +101,9 @@ public class AccountSigninActivity extends AppCompatActivity
                 || mAccessPoint == SigninAccessPoint.RECENT_TABS
                 || mAccessPoint == SigninAccessPoint.SETTINGS
                 || mAccessPoint == SigninAccessPoint.SIGNIN_PROMO
-                : "invalid access point: " + mAccessPoint;
+                || mAccessPoint
+                        == SigninAccessPoint.AUTOFILL_DROPDOWN : "invalid access point: "
+                                + mAccessPoint;
 
         mView = (AccountSigninView) LayoutInflater.from(this).inflate(
                 R.layout.account_signin_view, null);
@@ -173,6 +179,9 @@ public class AccountSigninActivity extends AppCompatActivity
 
     private void recordSigninStartedUserAction() {
         switch (getAccessPoint()) {
+            case SigninAccessPoint.AUTOFILL_DROPDOWN:
+                RecordUserAction.record("Signin_Signin_FromAutofillDropdown");
+                break;
             case SigninAccessPoint.BOOKMARK_MANAGER:
                 RecordUserAction.record("Signin_Signin_FromBookmarkManager");
                 break;