Make setRootId() persistent

Currently, changes by setRootId() in Tab are not reflected in TabState
and will be lost when tabs are restored. This CL fixes this issue.

Bug: 971327
Change-Id: Ia7daf36d4feb23f79b9c364d1232090671a7b9d2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1647134
Commit-Queue: Yue Zhang <yuezhanggg@google.com>
Reviewed-by: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#667239}

chrome/android/chrome_junit_test_java_sources.gni

@@ -178,6 +178,7 @@ chrome_junit_test_java_sources = [
   "junit/src/org/chromium/chrome/browser/suggestions/tile/TileGroupUnitTest.java",
   "junit/src/org/chromium/chrome/browser/survey/ChromeSurveyControllerTest.java",
   "junit/src/org/chromium/chrome/browser/tab/TabAttributesTest.java",
+  "junit/src/org/chromium/chrome/browser/tab/TabUnitTest.java",
   "junit/src/org/chromium/chrome/browser/tabmodel/TabPersistentStoreUnitTest.java",
   "junit/src/org/chromium/chrome/browser/tabstate/TabStateUnitTest.java",
   "junit/src/org/chromium/chrome/browser/tasks/EngagementTimeUtilTest.java",

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

@@ -166,4 +166,7 @@ public class EmptyTabObserver implements TabObserver {
 
     @Override
     public void onContentViewSystemUiVisibilityChanged(Tab tab, int visibility) {}
+
+    @Override
+    public void onRootIdChanged(Tab tab, int newRootId) {}
 }

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

@@ -643,7 +643,12 @@ public class Tab
      * @param rootId New relationship id to be set.
      */
     public void setRootId(int rootId) {
+        if (rootId == mRootId) return;
         mRootId = rootId;
+        mIsTabStateDirty = true;
+        for (TabObserver observer : mObservers) {
+            observer.onRootIdChanged(this, rootId);
+        }
     }
 
     /**

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

@@ -366,4 +366,10 @@ public interface TabObserver {
      * @see View#setSystemUiVisibility(int)
      */
     void onContentViewSystemUiVisibilityChanged(Tab tab, int visibility);
+
+    /**
+     * Called when the root Id of tab is changed.
+     * @param newRootId New root ID to be set.
+     */
+    void onRootIdChanged(Tab tab, int newRootId);
 }

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

@@ -203,6 +203,11 @@ public class TabModelSelectorImpl extends TabModelSelectorBase implements TabMod
             public void onCloseContents(Tab tab) {
                 closeTab(tab);
             }
+
+            @Override
+            public void onRootIdChanged(Tab tab, int newRootId) {
+                mTabSaver.addTabToSaveQueue(tab);
+            }
         };
     }
 

chrome/android/junit/src/org/chromium/chrome/browser/tab/TabUnitTest.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 static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+
+import android.app.Activity;
+import android.content.Context;
+import android.support.test.filters.SmallTest;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.annotation.Config;
+
+import org.chromium.base.test.BaseRobolectricTestRunner;
+import org.chromium.chrome.browser.ChromeFeatureList;
+import org.chromium.content_public.browser.LoadUrlParams;
+import org.chromium.ui.base.WindowAndroid;
+
+import java.lang.ref.WeakReference;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Tests for {@link Tab}.
+ */
+@RunWith(BaseRobolectricTestRunner.class)
+@Config(manifest = Config.NONE)
+public class TabUnitTest {
+    private static final int TAB1_ID = 456;
+    private static final int TAB2_ID = 789;
+
+    @Mock
+    private WindowAndroid mWindowAndroid;
+    @Mock
+    private LoadUrlParams mLoadUrlParams;
+    @Mock
+    private EmptyTabObserver mObserver;
+    @Mock
+    private Context mContext;
+    @Mock
+    private WeakReference<Context> mWeakReferenceContext;
+    @Mock
+    private WeakReference<Activity> mWeakReferenceActivity;
+    @Mock
+    private Activity mActivity;
+
+    private Tab mTab;
+
+    @Before
+    public void setUp() throws InterruptedException {
+        MockitoAnnotations.initMocks(this);
+
+        doReturn(mWeakReferenceActivity).when(mWindowAndroid).getActivity();
+        doReturn(mWeakReferenceContext).when(mWindowAndroid).getContext();
+        doReturn(mActivity).when(mWeakReferenceActivity).get();
+        doReturn(mContext).when(mWeakReferenceContext).get();
+        doReturn(mContext).when(mContext).getApplicationContext();
+
+        // Bypass feature checks.
+        Map<String, Boolean> features = new HashMap<>();
+        features.put("ShoppingAssist", true);
+        ChromeFeatureList.setTestFeatures(features);
+
+        mTab = new Tab(TAB1_ID, null, false, mWindowAndroid, null, null, mLoadUrlParams);
+        mTab.addObserver(mObserver);
+    }
+
+    @Test
+    @SmallTest
+    public void testSetRootIdWithChange() throws Exception {
+        assertThat(mTab.getRootId(), equalTo(TAB1_ID));
+
+        mTab.setRootId(TAB2_ID);
+
+        verify(mObserver).onRootIdChanged(mTab, TAB2_ID);
+        assertThat(mTab.getRootId(), equalTo(TAB2_ID));
+        assertThat(mTab.isTabStateDirty(), equalTo(true));
+    }
+
+    @Test
+    @SmallTest
+    public void testSetRootIdWithoutChange() throws Exception {
+        assertThat(mTab.getRootId(), equalTo(TAB1_ID));
+        mTab.setIsTabStateDirty(false);
+
+        mTab.setRootId(TAB1_ID);
+
+        verify(mObserver, never()).onRootIdChanged(any(Tab.class), anyInt());
+        assertThat(mTab.getRootId(), equalTo(TAB1_ID));
+        assertThat(mTab.isTabStateDirty(), equalTo(false));
+    }
+}