Android: TabParentIntent for intent handling

TabParentIntent encapsulates an Intent object with its triggering
logic for bring up the activity a tab was opened from.

Bug: 925242
Change-Id: Ib33e9f77744696b9026408c388e6e38b1345029b
Reviewed-on: https://chromium-review.googlesource.com/c/1472270
Commit-Queue: Jinsuk Kim <jinsukkim@chromium.org>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#634376}

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

@@ -76,6 +76,9 @@ public class EmptyTabObserver implements TabObserver {
     @Override
     public void onContextualActionBarVisibilityChanged(Tab tab, boolean visible) { }
 
+    @Override
+    public void onCloseContents(Tab tab) {}
+
     @Override
     public void onLoadStarted(Tab tab, boolean toDifferentDocument) { }
 

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

@@ -181,13 +181,6 @@ public class Tab
      */
     private int mRootId;
 
-    /**
-     * If this tab was opened from another tab in another Activity, this is the Intent that can be
-     * fired to bring the parent Activity back.
-     * TODO(dfalcantara): Remove this mechanism when we have a global TabManager.
-     */
-    private Intent mParentIntent;
-
     /**
      * Whether the tab should be grouped with its parent tab.
      */
@@ -2474,21 +2467,6 @@ public class Tab
         return 0;
     }
 
-    /**
-     * Sets the Intent that can be fired to restart the Activity of this Tab's parent.
-     * Should only be called if the Tab was launched via a different Activity.
-     */
-    public void setParentIntent(Intent parentIntent) {
-        mParentIntent = parentIntent;
-    }
-
-    /**
-     * @return Intent that can be fired to restart the parent Activity.
-     */
-    protected Intent getParentIntent() {
-        return mParentIntent;
-    }
-
     /**
      * Creates a new, "frozen" tab from a saved state. This can be used for background tabs restored
      * on cold start that should be loaded when switched to. initialize() needs to be called

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

@@ -161,6 +161,12 @@ public interface TabObserver {
 
     // WebContentsDelegateAndroid methods ---------------------------------------------------------
 
+    /**
+     * Called when the WebContents is closed.
+     * @param tab The notifying {@link Tab}.
+     */
+    void onCloseContents(Tab tab);
+
     /**
      * Called when the WebContents starts loading. Different from
      * {@link #onPageLoadStarted(Tab, String)}, if the user is navigated to a different url while

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

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.tab;
+
+import android.content.Intent;
+
+import org.chromium.base.UserData;
+import org.chromium.base.UserDataHost;
+
+/**
+ * A holder of {@link Intent} object to be used to bring back the parent {@link Activity}
+ * from which the associated tab was opened.
+ */
+public final class TabParentIntent extends EmptyTabObserver implements UserData {
+    private static final Class<TabParentIntent> USER_DATA_KEY = TabParentIntent.class;
+
+    private final Tab mTab;
+
+    /**
+     * If the associated tab was opened from another tab in another Activity, this is the Intent
+     * that can be fired to bring the parent Activity back.
+     */
+    private Intent mParentIntent;
+
+    public static TabParentIntent from(Tab tab) {
+        UserDataHost host = tab.getUserDataHost();
+        TabParentIntent tabParentIntent = host.getUserData(USER_DATA_KEY);
+        if (tabParentIntent == null) {
+            tabParentIntent = host.setUserData(USER_DATA_KEY, new TabParentIntent(tab));
+        }
+        return tabParentIntent;
+    }
+
+    private TabParentIntent(Tab tab) {
+        mTab = tab;
+        mTab.addObserver(this);
+    }
+
+    @Override
+    public void onCloseContents(Tab tab) {
+        boolean isSelected = mTab.getTabModelSelector().getCurrentTab() == tab;
+
+        // If the parent Tab belongs to another Activity, fire the Intent to bring it back.
+        if (isSelected && mParentIntent != null && tab.getActivity().getIntent() != mParentIntent) {
+            tab.getActivity().startActivity(mParentIntent);
+        }
+    }
+
+    public void set(Intent intent) {
+        mParentIntent = intent;
+    }
+
+    @Override
+    public void destroy() {
+        mTab.removeObserver(this);
+    }
+}

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

@@ -6,7 +6,6 @@ package org.chromium.chrome.browser.tab;
 
 import android.annotation.TargetApi;
 import android.app.Activity;
-import android.app.ActivityManager;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.Resources;
@@ -30,7 +29,6 @@ import org.chromium.chrome.R;
 import org.chromium.chrome.browser.AppHooks;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.SwipeRefreshHandler;
-import org.chromium.chrome.browser.document.DocumentUtils;
 import org.chromium.chrome.browser.document.DocumentWebContentsDelegate;
 import org.chromium.chrome.browser.findinpage.FindMatchRectsDetails;
 import org.chromium.chrome.browser.findinpage.FindNotificationDetails;
@@ -77,47 +75,23 @@ public class TabWebContentsDelegateAndroid extends WebContentsDelegateAndroid {
     /** Used for logging. */
     private static final String TAG = "WebContentsDelegate";
 
+    private final Runnable mCloseContentsRunnable;
     protected final Tab mTab;
 
+    protected Handler mHandler;
     private FindResultListener mFindResultListener;
-
     private FindMatchRectsListener mFindMatchRectsListener;
-
     private @WebDisplayMode int mDisplayMode = WebDisplayMode.BROWSER;
 
-    protected Handler mHandler;
-
-    private final Runnable mCloseContentsRunnable = new Runnable() {
-        @Override
-        public void run() {
-            boolean isSelected = mTab.getTabModelSelector().getCurrentTab() == mTab;
-            mTab.getTabModelSelector().closeTab(mTab);
-
-            // If the parent Tab belongs to another Activity, fire the Intent to bring it back.
-            if (isSelected && mTab.getParentIntent() != null
-                    && mTab.getActivity().getIntent() != mTab.getParentIntent()) {
-                mTab.getActivity().startActivity(mTab.getParentIntent());
-            }
-        }
-
-        /** If the API allows it, returns whether a Task still exists for the parent Activity. */
-        @TargetApi(Build.VERSION_CODES.LOLLIPOP)
-        private boolean isParentInAndroidOverview() {
-            ActivityManager activityManager = (ActivityManager) mTab.getApplicationContext()
-                    .getSystemService(Context.ACTIVITY_SERVICE);
-            for (ActivityManager.AppTask task : activityManager.getAppTasks()) {
-                Intent taskIntent = DocumentUtils.getBaseIntentFromTask(task);
-                if (taskIntent != null && taskIntent.filterEquals(mTab.getParentIntent())) {
-                    return true;
-                }
-            }
-            return false;
-        }
-    };
-
     public TabWebContentsDelegateAndroid(Tab tab) {
         mTab = tab;
         mHandler = new Handler();
+        mCloseContentsRunnable = () -> {
+            // TODO(jinsukkim): Move |closeTab| to TabModelSelector by making it observe its tabs.
+            mTab.getTabModelSelector().closeTab(mTab);
+            RewindableIterator<TabObserver> observers = mTab.getTabObservers();
+            while (observers.hasNext()) observers.next().onCloseContents(mTab);
+        };
     }
 
     /**

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

@@ -16,6 +16,7 @@ import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
 import org.chromium.chrome.browser.net.spdyproxy.DataReductionProxySettings;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tab.TabDelegateFactory;
+import org.chromium.chrome.browser.tab.TabParentIntent;
 import org.chromium.chrome.browser.tab.TabRedirectHandler;
 import org.chromium.chrome.browser.tab.TabState;
 import org.chromium.chrome.browser.util.IntentUtils;
@@ -132,7 +133,7 @@ public class ChromeTabCreator extends TabCreatorManager.TabCreator {
                         !openInForeground);
                 tab.initialize(
                         webContents, mTabContentManager, delegateFactory, !openInForeground, false);
-                tab.setParentIntent(parentIntent);
+                TabParentIntent.from(tab).set(parentIntent);
                 webContents.resumeLoadingCreatedWebContents();
             } else if (!openInForeground && SysUtils.isLowEndDevice()) {
                 // On low memory devices the tabs opened in background are not loaded automatically

chrome/android/java_sources.gni

@@ -1562,6 +1562,7 @@ chrome_java_sources = [
   "java/src/org/chromium/chrome/browser/tab/TabIdManager.java",
   "java/src/org/chromium/chrome/browser/tab/TabImportanceManager.java",
   "java/src/org/chromium/chrome/browser/tab/TabObserver.java",
+  "java/src/org/chromium/chrome/browser/tab/TabParentIntent.java",
   "java/src/org/chromium/chrome/browser/tab/TabRedirectHandler.java",
   "java/src/org/chromium/chrome/browser/tab/TabState.java",
   "java/src/org/chromium/chrome/browser/tab/TabStateBrowserControlsVisibilityDelegate.java",