Add tab reparenting

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

Index: chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java b/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
index 33b3ad40e8f7409be087937f66a876725f9d6e14..67535810e3ada8cce03f38ad662d5cf8327ae6d1 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tab/Tab.java
@@ -153,7 +153,7 @@ public final class Tab implements ViewGroup.OnHierarchyChangeListener,
     private final Context mThemedApplicationContext;
 
     /** Gives {@link Tab} a way to interact with the Android window. */
-    private final WindowAndroid mWindowAndroid;
+    private WindowAndroid mWindowAndroid;
 
     /** Whether or not this {@link Tab} is initialized and should be interacted with. */
     private boolean mIsInitialized;
@@ -1355,6 +1355,38 @@ public final class Tab implements ViewGroup.OnHierarchyChangeListener,
     }
 
     /**
+     * Detaches tab and related objects from an existing activity and attaches to a new one. This
+     * updates many delegates inside the tab and {@link ContentViewCore} both on java and native
+     * sides.
+     * @param activity The new activity this tab should be associated with.
+     * @param tabDelegateFactory The new delegate factory this tab should be using.
+     */
+    public void reparentToActivity(ChromeActivity activity, TabDelegateFactory tabDelegateFactory) {
+        ChromeActivity oldActivity = getActivity();
+
+        // Update and propagate for the new WindowAndroid.
+        mWindowAndroid = activity.getWindowAndroid();
+        mContentViewCore.updateWindowAndroid(mWindowAndroid);
+
+        // Update for the controllers that needs the Compositor from the new Activity.

[gone, 2016/02/24 18:40:37]

needs -> need

[Yusuf, 2016/02/24 19:40:35]

Done.

+        nativeAttachToTabContentManager(mNativeTabAndroid, activity.getTabContentManager());
+        mFullscreenManager = activity.getFullscreenManager();
+        activity.getCompositorViewHolder().onActiveTabReparented();
+
+        // Update the delegate factory, then recreate and propagate all delegates.
+        mDelegateFactory = tabDelegateFactory;
+        mWebContentsDelegate = mDelegateFactory.createWebContentsDelegate(this);
+        nativeUpdateDelegates(mNativeTabAndroid,
+                mWebContentsDelegate, mDelegateFactory.createContextMenuPopulator(this));
+        mTopControlsVisibilityDelegate = mDelegateFactory.createTopControlsVisibilityDelegate(this);
+        setInterceptNavigationDelegate(mDelegateFactory.createInterceptNavigationDelegate(this));
+        mAppBannerManager = mDelegateFactory.createAppBannerManager(this);

[gone, 2016/02/24 18:40:37]

You're not calling mAppBannerManager.destroy() on the old one, which has a
native pointer.  Are you missing any other destroy() calls for the ones you're
replacing?

[Yusuf, 2016/02/24 19:40:35]

Done.
No, the appbannermanager is the only one. And I had totally checked this all
before you told me to...

+
+        // Take down the old activity, which destroys all the remaining tabmodels and tabs.
+        if (oldActivity != null && !oldActivity.isActivityDestroyed()) oldActivity.finish();
+    }
+
+    /**
      * @return The delegate factory for testing purposes only.
      */
     public TabDelegateFactory getDelegateFactory() {
@@ -2945,6 +2977,8 @@ public final class Tab implements ViewGroup.OnHierarchyChangeListener,
     private native void nativeInitWebContents(long nativeTabAndroid, boolean incognito,
             ContentViewCore contentViewCore, TabWebContentsDelegateAndroid delegate,
             ContextMenuPopulator contextMenuPopulator);
+    private native void nativeUpdateDelegates(long nativeTabAndroid,
+            TabWebContentsDelegateAndroid delegate, ContextMenuPopulator contextMenuPopulator);
     private native void nativeDestroyWebContents(long nativeTabAndroid, boolean deleteNative);
     private native Profile nativeGetProfileAndroid(long nativeTabAndroid);
     private native int nativeLoadUrl(long nativeTabAndroid, String url, String extraHeaders,