📺 Move fullscreen web content to a new Activity.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/tab/TabWebContentsDelegateAndroid.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tab/TabWebContentsDelegateAndroid.java b/chrome/android/java/src/org/chromium/chrome/browser/tab/TabWebContentsDelegateAndroid.java
index 6c6188991500c9ed886f643663a13bed8d8115b5..cd3452daee613bebf3e85c59e08021ac961c2b6b 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tab/TabWebContentsDelegateAndroid.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tab/TabWebContentsDelegateAndroid.java
@@ -24,6 +24,8 @@ import org.chromium.base.annotations.CalledByNative;
 import org.chromium.blink_public.platform.WebDisplayMode;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.AppHooks;
+import org.chromium.chrome.browser.ChromeTabbedActivity;
+import org.chromium.chrome.browser.FullscreenWebContentsActivity;
 import org.chromium.chrome.browser.RepostFormWarningDialog;
 import org.chromium.chrome.browser.document.DocumentUtils;
 import org.chromium.chrome.browser.document.DocumentWebContentsDelegate;
@@ -32,6 +34,7 @@ import org.chromium.chrome.browser.findinpage.FindNotificationDetails;
 import org.chromium.chrome.browser.fullscreen.FullscreenManager;
 import org.chromium.chrome.browser.media.MediaCaptureNotificationService;
 import org.chromium.chrome.browser.media.VideoPersister;
+import org.chromium.chrome.browser.multiwindow.MultiWindowUtils;
 import org.chromium.chrome.browser.policy.PolicyAuditor;
 import org.chromium.chrome.browser.policy.PolicyAuditor.AuditEvent;
 import org.chromium.chrome.browser.tabmodel.TabCreatorManager.TabCreator;
@@ -214,9 +217,45 @@ public class TabWebContentsDelegateAndroid extends WebContentsDelegateAndroid {
     }
 
     @Override
-    public void toggleFullscreenModeForTab(boolean enableFullscreen) {
-        if (!VideoPersister.getInstance().shouldDelayFullscreenModeChange(mTab, enableFullscreen)) {
-            mTab.toggleFullscreenMode(enableFullscreen);
+    public void toggleFullscreenModeForTab(final boolean enableFullscreen) {
+        // TODO(peconn): Change this to the flag.
+        final boolean useFullscreenActivity = true;
+        if (useFullscreenActivity && mTab.getActivity().supportsFullscreenActivity()) {
+            if (mTab.getFullscreenManager() == null) {
+                Log.d(TAG, "Cannot toggle fullscreen, Manager is null.");
+                return;
+            }
+
+            Class<? extends Activity> targetActivity;
+            if (enableFullscreen) {
+                targetActivity = FullscreenWebContentsActivity.class;
+            } else {
+                targetActivity = MultiWindowUtils.getSenderActivity(mTab.getActivity());
+                if (targetActivity == null) {
+                    Log.w(TAG, "Tab exiting fullscreen without sender Activity.");
+                    targetActivity = ChromeTabbedActivity.class;
+                }
+            }
+
+            if (mTab.getFullscreenManager().getTab() == mTab) {
+                mTab.getFullscreenManager().setTab(null);
+            }
+
+            MultiWindowUtils.moveTabToActivity(

[Theresa, 2017/04/12 22:29:11]

Does the fullscreen activity sit on top of the parent ChromeTabbedActivity (part
of the same task)? If so, please disregard the rest of this comment.

If not, we probably want to introduce logic to determine if the task for the
parent activity is still running before moving the tab. Previously when moving
tabs between windows, if the activity for the other window didn't already exist
it was always correct to create it (E.g. when the user selects "Open in Chrome"
in a CCT or "Move to other window" from the app menu in Chrome).

If the fullscreen activity is a separate task you'll need to handle this
scenario:

1. Go into multi-window mode, create ChromeTabbedActivity2
2. Fullscreen a tab in ChromeTabbedActivity2 creating a separate task for
FullscreenWebContentsActivity
3. Kill ChromeTabbedActivity2, exit multi-window mode
4. Exit fullscreen on the tab -- at this point, it's invalid to recreate
ChromeTabbedActivtiy2, so we want the tab to get reparented into
ChromeTabbedActivity.

[PEConn, 2017/04/13 14:45:57]

I was planning on having the fullscreen Activity be part of the same task - it
seems to make more sense. Will Android ever kill background Activities in the
same task as the foreground one?

Would there be any advantages to having the fullscreen Activity *not* be in the
same task?

[Theresa, 2017/04/13 15:22:09]

I don't think Android will kill the background activity. It will be stopped and
have a saved instance state. In this case it doesn't matter, because the
scenario laid out requires the user to remove the task from Android Recents.

Outside of PIP, I don't see any advantages of making the  fullscreen activity a
separate task. Once fullscreen activity is PIPed, though, does it become a
separate task? If not, what does tapping on the Chrome launcher icon do?

+                    mTab.getActivity(), mTab, targetActivity, new Runnable() {
+                        @Override
+                        public void run() {
+                            // The Tab's FullscreenManager changes when it is moved.
+                            mTab.getFullscreenManager().setTab(mTab);
+
+                            mTab.toggleFullscreenMode(enableFullscreen);
+                        }
+                    });
+        } else {
+            if (!VideoPersister.getInstance().shouldDelayFullscreenModeChange(
+                        mTab, enableFullscreen)) {
+                mTab.toggleFullscreenMode(enableFullscreen);
+            }
         }
     }