Added code to support launch new tab with context menu

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

Index: chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java
diff --git a/chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java b/chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java
index 8dc755b2df7914bd080ca3e9a375b64e5138cc78..668052dbb3983e013ea9dc82eab75ed3c1f96932 100644
--- a/chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java
+++ b/chrome/android/shell/java/src/org/chromium/chrome/shell/TabManager.java
@@ -76,6 +76,7 @@ public class TabManager extends LinearLayout {
 
         mTabModelSelector = new ChromeShellTabModelSelector(
                 window, videoViewClient, mContentViewHolder);
+        mTabModelSelector.setTabManager(this);

[Bernhard Bauer, 2014/10/30 13:41:35]

Any reason you're using a mutator here instead of passing it into the
constructor?

[ankit, 2014/10/30 14:16:46]

I just thought if ChromeShellTabModelSelector is created by any other place in
future for testing purpose which does not require to maintan TabManager object
then it will be an addition task to do that. To avoid changing constructor I
have used mutator. 
Please suggest your opinion 

[Bernhard Bauer, 2014/10/31 11:22:36]

Eh. I would rather allow ChromeShellTabModelSelector to assume that its
TabManager is always non-null (you might have noticed I don't like having silent
null-checks all over the place). If we want to use ChromeShellTabModelSelector
without a TabManager in the future, we can still refactor it then.

         mTabModelSelector.getModel(false).addObserver(mTabModelObserver);
 
         mToolbar = (ChromeShellToolbar) findViewById(R.id.toolbar);