[Instant Start] Add PseudoTab

PseudoTab represents Tab-like cards in the Grid Tab Switcher. It can
be used to represent a card before the Tab objects are constructed.

Bug: 1016952
Change-Id: I908dbe70dae6af691ae45ab3342701b4995220bd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1874708
Commit-Queue: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#708736}

chrome/android/features/tab_ui/BUILD.gn

@@ -83,6 +83,7 @@ android_library("java") {
     "java/src/org/chromium/chrome/browser/tasks/TasksSurfaceCoordinator.java",
     "java/src/org/chromium/chrome/browser/tasks/TasksView.java",
     "java/src/org/chromium/chrome/browser/tasks/TasksViewBinder.java",
+    "java/src/org/chromium/chrome/browser/tasks/pseudotab/PseudoTab.java",
     "java/src/org/chromium/chrome/browser/tasks/pseudotab/TabAttributeCache.java",
     "java/src/org/chromium/chrome/browser/tasks/tab_groups/TabGroupUtils.java",
     "java/src/org/chromium/chrome/browser/tasks/tab_management/ClosableTabGridView.java",

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/pseudotab/PseudoTab.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.tasks.pseudotab;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import org.chromium.chrome.browser.tab.Tab;
+import org.chromium.chrome.browser.tabmodel.TabList;
+import org.chromium.chrome.browser.tabmodel.TabModelFilter;
+import org.chromium.chrome.browser.tabmodel.TabModelFilterProvider;
+import org.chromium.chrome.browser.util.FeatureUtilities;
+
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.WeakHashMap;
+
+/**
+ * Representation of a Tab-like card in the Grid Tab Switcher.
+ */
+public class PseudoTab {
+    private final Integer mTabId;
+    private final WeakReference<Tab> mTab;
+    private static final WeakHashMap<Integer, PseudoTab> sAllTabs = new WeakHashMap<>();
+
+    /**
+     * An interface to get the title to be used for a tab.
+     */
+    public interface TitleProvider { String getTitle(PseudoTab tab); }
+
+    /**
+     * Construct from a tab ID. An earlier instance with the same ID can be returned.
+     */
+    public static PseudoTab fromTabId(int tabId) {
+        PseudoTab cached = sAllTabs.get(tabId);
+        if (cached != null) return cached;
+        return new PseudoTab(tabId);
+    }
+
+    private PseudoTab(int tabId) {
+        mTabId = tabId;
+        mTab = null;
+        sAllTabs.put(getId(), this);
+    }
+
+    /**
+     * Construct from a {@link Tab}. An earlier instance with the same {@link Tab} can be returned.
+     */
+    public static PseudoTab fromTab(@NonNull Tab tab) {
+        PseudoTab cached = sAllTabs.get(tab.getId());
+        if (cached != null && cached.hasRealTab()) {
+            assert cached.getTab() == tab;
+            return cached;
+        }
+        // We need to upgrade a pre-native Tab to a post-native Tab.
+        return new PseudoTab(tab);
+    }
+
+    private PseudoTab(@NonNull Tab tab) {
+        mTabId = tab.getId();
+        mTab = new WeakReference<>(tab);
+        sAllTabs.put(getId(), this);
+    }
+
+    /**
+     * Convert a list of {@link Tab} to a list of {@link PseudoTab}.
+     * @param tabs A list of {@link Tab}
+     * @return A list of {@link PseudoTab}
+     */
+    public static List<PseudoTab> getListOfPseudoTab(@Nullable List<Tab> tabs) {
+        List<PseudoTab> pseudoTabs = null;
+        if (tabs != null) {
+            pseudoTabs = new ArrayList<>();
+            for (Tab tab : tabs) {
+                pseudoTabs.add(fromTab(tab));
+            }
+        }
+        return pseudoTabs;
+    }
+
+    /**
+     * Convert a {@link TabList} to a list of {@link PseudoTab}.
+     * @param tabList A {@link TabList}
+     * @return A list of {@link PseudoTab}
+     */
+    public static List<PseudoTab> getListOfPseudoTab(@Nullable TabList tabList) {
+        List<PseudoTab> pseudoTabs = null;
+        if (tabList != null) {
+            pseudoTabs = new ArrayList<>();
+            for (int i = 0; i < tabList.getCount(); i++) {
+                pseudoTabs.add(fromTab(tabList.getTabAt(i)));
+            }
+        }
+        return pseudoTabs;
+    }
+
+    @Override
+    public String toString() {
+        assert mTabId != null;
+        return "Tab " + mTabId;
+    }
+
+    /**
+     * @return The ID of the {@link PseudoTab}
+     */
+    public int getId() {
+        return mTabId;
+    }
+
+    /**
+     * Get the title of the {@link PseudoTab} through a {@link TitleProvider}.
+     *
+     * If the {@link TitleProvider} is {@code null}, fall back to {@link #getTitle()}.
+     * @param titleProvider The {@link TitleProvider} to provide the title.
+     * @return The title
+     */
+    public String getTitle(@Nullable TitleProvider titleProvider) {
+        if (titleProvider != null) return titleProvider.getTitle(this);
+        return getTitle();
+    }
+
+    /**
+     * Get the title of the {@link PseudoTab}.
+     * @return The title
+     */
+    public String getTitle() {
+        if (mTab != null && mTab.get() != null) {
+            return mTab.get().getTitle();
+        }
+        assert mTabId != null;
+        return TabAttributeCache.getTitle(mTabId);
+    }
+
+    /**
+     * Get the URL of the {@link PseudoTab}.
+     * @return The URL
+     */
+    public String getUrl() {
+        if (mTab != null && mTab.get() != null) {
+            return mTab.get().getUrl();
+        }
+        assert mTabId != null;
+        return TabAttributeCache.getUrl(mTabId);
+    }
+
+    /**
+     * Get the root ID of the {@link PseudoTab}.
+     * @return The root ID
+     */
+    public int getRootId() {
+        if (mTab != null && mTab.get() != null) {
+            return mTab.get().getRootId();
+        }
+        assert mTabId != null;
+        return TabAttributeCache.getRootId(mTabId);
+    }
+
+    /**
+     * @return Whether the {@link PseudoTab} is in the Incognito mode.
+     */
+    public boolean isIncognito() {
+        if (mTab != null && mTab.get() != null) return mTab.get().isIncognito();
+        assert mTabId != null;
+        return false;
+    }
+
+    /**
+     * @return {@link Tab#getTimestampMillis()} of the underlying real {@link Tab}
+     */
+    public long getTimestampMillis() {
+        assert mTab != null
+                && mTab.get() != null : "getTimestampMillis can only be used with real tabs";
+        return mTab.get().getTimestampMillis();
+    }
+
+    /**
+     * @return Whether an underlying real {@link Tab} is available.
+     */
+    public boolean hasRealTab() {
+        return getTab() != null;
+    }
+
+    /**
+     * Get the underlying real {@link Tab}. We should avoid using this.
+     * @return The underlying real {@link Tab}.
+     */
+    @Deprecated
+    public @Nullable Tab getTab() {
+        if (mTab != null) return mTab.get();
+        return null;
+    }
+
+    /**
+     * Get related tabs of a certain {@link PseudoTab}, through {@link TabModelFilter}s if
+     * available.
+     * @param member The {@link PseudoTab} related to
+     * @param provider The {@link TabModelFilterProvider} to query the tab relation
+     * @return Related {@link PseudoTab}s
+     */
+    public static @NonNull List<PseudoTab> getRelatedTabs(
+            PseudoTab member, @NonNull TabModelFilterProvider provider) {
+        List<Tab> relatedTabs = getRelatedTabList(provider, member.getId());
+        if (relatedTabs != null) return getListOfPseudoTab(relatedTabs);
+
+        List<PseudoTab> related = new ArrayList<>();
+        int rootId = member.getRootId();
+        if (rootId == Tab.INVALID_TAB_ID || !FeatureUtilities.isTabGroupsAndroidEnabled()) {
+            related.add(member);
+            return related;
+        }
+        for (Integer key : sAllTabs.keySet()) {
+            PseudoTab tab = sAllTabs.get(key);
+            assert tab != null;
+            if (tab.getRootId() == Tab.INVALID_TAB_ID) continue;
+            if (tab.getRootId() != rootId) continue;
+            related.add(tab);
+        }
+        assert related.size() > 0;
+        return related;
+    }
+
+    private static @Nullable List<Tab> getRelatedTabList(
+            @NonNull TabModelFilterProvider provider, int tabId) {
+        if (provider.getTabModelFilter(false) != null) {
+            List<Tab> related = provider.getTabModelFilter(false).getRelatedTabList(tabId);
+            if (related.size() > 0) return related;
+        }
+        if (provider.getTabModelFilter(true) != null) {
+            List<Tab> related = provider.getTabModelFilter(true).getRelatedTabList(tabId);
+            assert related.size() > 0;
+            return related;
+        }
+        return null;
+    }
+}

chrome/android/features/tab_ui/tab_management_java_sources.gni

@@ -35,6 +35,7 @@ tab_management_test_java_sources = [
 
 tab_management_junit_java_sources = [
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/MostVisitedListViewBinderUnitTest.java",
+  "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/pseudotab/PseudoTabUnitTest.java",
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/pseudotab/TabAttributeCacheUnitTest.java",
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/tab_groups/TabGroupModelFilterUnitTest.java",
   "//chrome/android/features/tab_ui/junit/src/org/chromium/chrome/browser/tasks/tab_groups/TabGroupUtilsUnitTest.java",