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 9c4ac52484b99f412402644971cdf37cdbf94169..93ec5e1ae515dae2503585976994791f3e167e71 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
@@ -156,7 +156,7 @@ 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;
@@ -1358,6 +1358,35 @@ 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) {

[Ted C, 2016/02/26 18:46:29]

we might want this to be a two part call eventually.

one is disconnectFromActivity and connectToActivity where they would be
symmetric.

Follow up.

[Yusuf, 2016/02/26 19:39:52]

Acknowledged.

+        // TODO(yusufo): Share these calls with the construction related calls.
+
+        // Update and propagate for the new WindowAndroid.
+        mWindowAndroid = activity.getWindowAndroid();
+        mContentViewCore.updateWindowAndroid(mWindowAndroid);
+
+        // Update for the controllers that need the Compositor from the new Activity.
+        nativeAttachToTabContentManager(mNativeTabAndroid, activity.getTabContentManager());
+        mFullscreenManager = activity.getFullscreenManager();
+        activity.getCompositorViewHolder().prepareForTabReparenting();
+
+        // 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);
+    }
+
+    /**
      * @return The delegate factory for testing purposes only.
      */
     public TabDelegateFactory getDelegateFactory() {
@@ -2949,6 +2978,8 @@ 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,