Add tab reparenting

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

Index: chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModel.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModel.java b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModel.java
index 287af15da2dbd4d85b8fc6fd351c2b37c48ffe8d..dced692244dd1757add5f1599c5bad8b8c3b3f09 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModel.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModel.java
@@ -47,7 +47,12 @@ public interface TabModel extends TabList {
          * Opened from the long press context menu.  Will not be brought to the foreground.
          * Like FROM_CHROME_UI, but also sets up a parent/child relationship like FROM_LINK.
          */
-        FROM_LONGPRESS_BACKGROUND
+        FROM_LONGPRESS_BACKGROUND,
+
+        /**
+         * Changed windows by moving from one activity to another. Will be opened in the foreground.
+         */
+        FROM_REPARENTING
     }
 
     /**
@@ -181,6 +186,13 @@ public interface TabModel extends TabList {
     void addTab(Tab tab, int index, TabLaunchType type);
 
     /**
+     * Removes the given tab from the model without destroying it. The tab should be inserted into
+     * another model to avoid leaking as after this the link to the old Activity will be broken.
+     * @param tab The tab to remove.
+     */
+    void removeTab(Tab tab);
+
+    /**
      * Subscribes a {@link TabModelObserver} to be notified about changes to this model.
      * @param observer The observer to be subscribed.
      */