Make content shell on android support relaunching.

content/shell/android/java/src/org/chromium/content_shell/ShellManager.java

Index: content/shell/android/java/src/org/chromium/content_shell/ShellManager.java
diff --git a/content/shell/android/java/src/org/chromium/content_shell/ShellManager.java b/content/shell/android/java/src/org/chromium/content_shell/ShellManager.java
index 082e99efa54675939be6835590f05ce427a4366f..feb6c84963a566cd0877d4562fe11c1357ea8423 100644
--- a/content/shell/android/java/src/org/chromium/content_shell/ShellManager.java
+++ b/content/shell/android/java/src/org/chromium/content_shell/ShellManager.java
@@ -35,6 +35,14 @@ public class ShellManager extends FrameLayout {
         return mActiveShell;
     }
 
+    /**
+     * Creates a new shell pointing to the specified URL.
+     * @param url The URL the shell should load upon creation.
+     */
+    public void launchShell(String url) {
+        nativeLaunchShell(url);
+    }
+
     @SuppressWarnings("unused")
     @CalledByNative
     private Object createShell() {
@@ -51,4 +59,5 @@ public class ShellManager extends FrameLayout {
     }
 
     private static native void nativeInit(Object shellManagerInstance);
+    private static native void nativeLaunchShell(String url);
 }