Adding an explicit listener for the VR mode close button

chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
index 9fcaf3e525168bb182e9bbdbde589706c360de51..587053feceaa0dae5c1b7b8f1d848814c4d27ef6 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
@@ -349,6 +349,11 @@ public class VrShellImpl extends GvrLayout implements GLSurfaceView.Renderer, Vr
         return this;
     }
 
+    @Override
+    public void setCloseButtonListener(Runnable runner) {
+        getUiLayout().setCloseButtonListener(runner);
+    }
+
     /**
      * Create a new GLES11Ext.GL_TEXTURE_EXTERNAL_OES texture handle.
      * @return New texture handle.