Opening new "about:blank" tab if all tabs are closed in tab switcher mode.

chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java

 // 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.shell;
 
 import android.content.Context;
 import android.util.AttributeSet;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewParent;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.FrameLayout;
 import android.widget.LinearLayout;
 
+import org.chromium.base.VisibleForTesting;
 import org.chromium.chrome.browser.EmptyTabObserver;
 import org.chromium.chrome.browser.Tab;
 import org.chromium.chrome.browser.tabmodel.EmptyTabModelObserver;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabLaunchType;
 import org.chromium.chrome.browser.tabmodel.TabModel.TabSelectionType;
 import org.chromium.chrome.browser.widget.accessibility.AccessibilityTabModelWrapper;
 import org.chromium.content.browser.ContentVideoViewClient;
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content.browser.ContentViewRenderView;
 import org.chromium.content_public.browser.LoadUrlParams;
@@ skipping 23 matching lines @@
         @Override
         public void didSelectTab(Tab tab, TabSelectionType type, int lastId) {
             assert tab instanceof ChromeShellTab;
             setCurrentTab((ChromeShellTab) tab);
             hideTabSwitcher();
         }
 
         @Override
         public void willCloseTab(Tab tab, boolean animate) {
             if (tab == mCurrentTab) setCurrentTab(null);
+            if (mTabModelSelector.getCurrentModel().getCount() == 1) {
+                createNewTab();
+            }
         }
     };
 
     /**
      * @param context The Context the view is running in.
      * @param attrs   The attributes of the XML tag that is inflating the view.
      */
     public TabManager(Context context, AttributeSet attrs) {
         super(context, attrs);
     }
@@ skipping 67 matching lines @@
         createTab("about:blank", TabLaunchType.FROM_MENU_OR_OVERVIEW);
     }
 
     /**
      * Closes all current tabs.
      */
     public void closeAllTabs() {
         mTabModelSelector.getCurrentModel().closeAllTabs();
     }
 
+    @VisibleForTesting
+    public void closeTab() {
+        mTabModelSelector.getCurrentModel().closeTab(mCurrentTab);
+    }
+
     /**
      * Creates a {@link ChromeShellTab} with a URL specified by {@code url}.
      * @param url The URL the new {@link ChromeShellTab} should start with.
      * @return The newly created tab, or null if the content view is uninitialized.
      */
     public Tab createTab(String url, TabLaunchType type) {
         if (!isContentViewRenderViewInitialized()) return null;
 
         LoadUrlParams loadUrlParams = new LoadUrlParams(url);
         Tab tab = mTabModelSelector.openNewTab(loadUrlParams, type, null, false);
@@ skipping 92 matching lines @@
         LoadUrlParams loadUrlParams = new LoadUrlParams(url);
         loadUrlParams.setTransitionType(PageTransition.TYPED | PageTransition.FROM_ADDRESS_BAR);
         Tab tab = mTabModelSelector.getCurrentTab();
         if (tab != null) {
             tab.loadUrl(loadUrlParams);
             return tab;
         }
         return createTab(url, TabLaunchType.FROM_KEYBOARD);
     }
 }