Upstream base implementations of TabModel, TabModelSelector, and TabModelObserver.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorBase.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorBase.java b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorBase.java
new file mode 100644
index 0000000000000000000000000000000000000000..6a6974ec64845b0bc9f021f0a55035927945ad46
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelSelectorBase.java
@@ -0,0 +1,171 @@
+// Copyright 2014 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.tabmodel;
+
+import org.chromium.chrome.browser.Tab;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Implement methods shared across the different model implementations.
+ */
+public abstract class TabModelSelectorBase implements TabModelSelector {
+    public static final int NORMAL_TAB_MODEL_INDEX = 0;
+    public static final int INCOGNITO_TAB_MODEL_INDEX = 1;
+
+    private List<TabModel> mTabModels = Collections.emptyList();
+    private int mActiveModelIndex = NORMAL_TAB_MODEL_INDEX;
+    private final ArrayList<ChangeListener> mChangeListeners = new ArrayList<ChangeListener>();
+
+    protected final void initialize(boolean startIncognito, TabModel... models) {
+        // Only normal and incognito supported for now.
+        assert mTabModels.isEmpty();
+        assert models.length > 0;
+        if (startIncognito) {
+            assert models.length > INCOGNITO_TAB_MODEL_INDEX;
+        }
+
+        List<TabModel> tabModels = new ArrayList<TabModel>();
+        for (int i = 0; i < models.length; i++) {
+            tabModels.add(models[i]);
+        }
+        mActiveModelIndex = startIncognito ? INCOGNITO_TAB_MODEL_INDEX : NORMAL_TAB_MODEL_INDEX;
+        mTabModels = Collections.unmodifiableList(tabModels);
+    }
+
+    @Override
+    public void selectModel(boolean incognito) {
+        mActiveModelIndex = incognito ? INCOGNITO_TAB_MODEL_INDEX : NORMAL_TAB_MODEL_INDEX;
+    }
+
+    @Override
+    public TabModel getModelAt(int index) {
+        assert (index < mTabModels.size() && index >= 0) :
+            "requested index " + index + " size " + mTabModels.size();
+        return mTabModels.get(index);
+    }
+
+    @Override
+    public Tab getCurrentTab() {
+        return getCurrentModel() == null ? null : TabModelUtils.getCurrentTab(getCurrentModel());
+    }
+
+    @Override
+    public int getCurrentTabId() {
+        Tab tab = getCurrentTab();
+        return tab != null ? tab.getId() : Tab.INVALID_TAB_ID;
+    }
+
+    @Override
+    public TabModel getModelForTabId(int id) {
+        for (int i = 0; i < mTabModels.size(); i++) {
+            TabModel model = mTabModels.get(i);
+            if (TabModelUtils.getTabById(model, id) != null || model.isClosurePending(id)) {
+                return model;
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public TabModel getCurrentModel() {
+        return getModelAt(mActiveModelIndex);
+    }
+
+    @Override
+    public int getCurrentModelIndex() {
+        return mActiveModelIndex;
+    }
+
+    @Override
+    public TabModel getModel(boolean incognito) {
+        int index = incognito ? INCOGNITO_TAB_MODEL_INDEX : NORMAL_TAB_MODEL_INDEX;
+        return getModelAt(index);
+    }
+
+    @Override
+    public boolean isIncognitoSelected() {
+        return mActiveModelIndex == INCOGNITO_TAB_MODEL_INDEX;
+    }
+
+    @Override
+    public List<TabModel> getModels() {
+        return mTabModels;
+    }
+
+    @Override
+    public boolean closeTab(Tab tab) {
+        for (int i = 0; i < getModels().size(); i++) {
+            TabModel model = getModelAt(i);
+            if (model.indexOf(tab) >= 0) {
+                return model.closeTab(tab);
+            }
+        }
+        assert false : "Tried to close a tab that is not in any model!";
+        return false;
+    }
+
+    @Override
+    public void commitAllTabClosures() {
+        for (int i = 0; i < mTabModels.size(); i++) {
+            mTabModels.get(i).commitAllTabClosures();
+        }
+    }
+
+    @Override
+    public Tab getTabById(int id) {
+        for (int i = 0; i < getModels().size(); i++) {
+            Tab tab = TabModelUtils.getTabById(getModelAt(i), id);
+            if (tab != null) return tab;
+        }
+        return null;
+    }
+
+    @Override
+    public void closeAllTabs() {
+        for (int i = 0; i < getModels().size(); i++) getModelAt(i).closeAllTabs();
+    }
+
+    @Override
+    public int getTotalTabCount() {
+        int count = 0;
+        for (int i = 0; i < getModels().size(); i++)  {
+            count += getModelAt(i).getCount();
+        }
+        return count;
+    }
+
+    @Override
+    public void registerChangeListener(ChangeListener changeListener) {
+        if (!mChangeListeners.contains(changeListener)) mChangeListeners.add(changeListener);
+    }
+
+    @Override
+    public void unregisterChangeListener(ChangeListener changeListener) {
+        mChangeListeners.remove(changeListener);
+    }
+
+    /**
+     * Notifies all the listeners that the {@link TabModelSelector} or its {@link TabModel} has
+     * changed.
+     */
+    protected void notifyChanged() {
+        for (int i = 0; i < mChangeListeners.size(); i++) {
+            mChangeListeners.get(i).onChange();
+        }
+    }
+
+    /**
+     * Notifies all the listeners that a new tab has been created.
+     * @param tab The tab that has been created.
+     */
+    protected void notifyNewTabCreated(Tab tab) {
+        for (int i = 0; i < mChangeListeners.size(); i++) {
+            mChangeListeners.get(i).onNewTabCreated(tab);
+        }
+    }
+}