Add tab persistence support for CustomTabs.

chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
index 36ad1bdddfd1a971eb6016288c3954f033f64d18..c8726db063dc7104a9cb076bd784f1088748c738 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorImpl.java
@@ -227,6 +227,17 @@ public class TabModelSelectorImpl extends TabModelSelectorBase implements TabMod
         };
     }
 
+    /**
+     * Exposed to allow tests to initialize the selector with different tab models.
+     * @param normalModel The normal tab model.
+     * @param incognitoModel The incognito tab model.
+     */
+    @VisibleForTesting
+    public void initializeForTesting(TabModel normalModel, TabModel incognitoModel) {
+        initialize(isIncognitoSelected(), normalModel, incognitoModel);
+        mActiveState = true;
+    }
+
     @Override
     public void setCloseAllTabsDelegate(CloseAllTabsDelegate delegate) {
         mCloseAllTabsDelegate = delegate;