Shortcut ctrl+shift+T added on android.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelImpl.java
index 85f5a65bc85bf78cee4009a29482dec305e01974..d166ee2425e185534cd8c24881bb4708e87770eb 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelImpl.java
@@ -9,6 +9,7 @@ import org.chromium.base.ObserverList;
 import org.chromium.base.TraceEvent;
 import org.chromium.chrome.browser.ChromeTabbedActivity;
 import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
+import org.chromium.chrome.browser.ntp.RecentlyClosedBridge;
 import org.chromium.chrome.browser.partnercustomizations.HomepageManager;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tabmodel.TabCreatorManager.TabCreator;
@@ -45,6 +46,7 @@ public class TabModelImpl extends TabModelJniBridge {
     private final TabPersistentStore mTabSaver;
     private final TabModelDelegate mModelDelegate;
     private final ObserverList<TabModelObserver> mObservers;
+    private RecentlyClosedBridge mRecentlyClosedBridge;
 
     // Undo State Tracking -------------------------------------------------------------------------
 
@@ -81,6 +83,7 @@ public class TabModelImpl extends TabModelJniBridge {
         mModelDelegate = modelDelegate;
         mIsUndoSupported = supportUndo;
         mObservers = new ObserverList<TabModelObserver>();
+        mRecentlyClosedBridge = new RecentlyClosedBridge(getProfile());
     }
 
     @Override
@@ -99,7 +102,7 @@ public class TabModelImpl extends TabModelJniBridge {
         mRewoundList.destroy();
         mTabs.clear();
         mObservers.clear();
-
+        mRecentlyClosedBridge.destroy();
         super.destroy();
     }
 
@@ -721,7 +724,7 @@ public class TabModelImpl extends TabModelJniBridge {
     protected boolean createTabWithWebContents(Tab parent, boolean incognito,
             WebContents webContents, int parentId) {
         return getTabCreator(incognito).createTabWithWebContents(parent, webContents, parentId,
-                TabLaunchType.FROM_LONGPRESS_BACKGROUND);
+                TabLaunchType.FROM_LONGPRESS_FOREGROUND);

[Theresa, 2016/06/29 23:53:29]

I suspect that changing this affects other places that were originally relying
on this method to open things in the background.

[xingliu, 2016/06/30 05:43:55]

Used to investigate this a little bit, this change make the restore tab to the
foreground when using tab restore service code in c++. In java, it seems we have
other class manage the tab ordering(and I guess foreground and ordering are
totally manged in java because they are android UI). And this enum seems totally
serve for other purpose.

I agree to put a TODO here to figure out if this break anything.

However, the worst case scenario I can think of is, this stuff might make
restored pages running javascripts in the background.

[Theresa, 2016/06/30 20:50:24]

If you go to "Recent tabs", long press on a recently closed tab or a tab from
another device and select "Open in new tab" previously this opened in the
background but with this patch it opens in the foreground.

For phones in particular, I think we want to retain the open in background
behavior so that this use case doesn't break:
1. Go to recents
2. Open a bunch of things in new tabs in the background
3. Look through newly created tabs.

This method could take a new parameter indicating whether the tab should open in
the foreground or background.

I think we should make sure UX agrees that ctrl+shift+t tabs should restore in
the foreground before adding the plumbing. I can introduce you to rolfe@ this
afternoon or tomorrow if we don't hear back soon :)

     }
 
     @Override
@@ -738,4 +741,23 @@ public class TabModelImpl extends TabModelJniBridge {
     protected boolean isSessionRestoreInProgress() {
         return mModelDelegate.isSessionRestoreInProgress();
     }
+
+    /**
+     * Open most recent closed tab. first check if android tab model has pending closures.
+     * if not, use native code to fetch data from tab restore service.
+     */
+    @Override
+    public void openRecentClosedTab() {
+        // recover tab from rewind list in java, same as the undo snackbar.

[Theresa, 2016/06/29 23:53:29]

nit: use proper sentence capitalization/punctuation for comments e.g. "First try
to recover the tab from the rewound list."

http://source.android.com/source/code-style.html#use-javadoc-standard-comments

[xingliu, 2016/06/30 05:43:55]

Done.

+        // {@link UndoBarController}.
+        if (mRewoundList.hasPendingClosures()) {
+            Tab tab = mRewoundList.getNextRewindableTab();
+            if (tab == null) return;
+            cancelTabClosure(tab.getId());
+            return;
+        }
+
+        // if no pending closure in java, open it from tab restore service in native code.

[Theresa, 2016/06/29 23:53:29]

nit: "If there are no pending closures in Java, ..."

[xingliu, 2016/06/30 05:43:55]

Done.

+        mRecentlyClosedBridge.openRecentClosedTab();
+    }
 }