Enable VR Shell for release build too

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

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShell.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShell.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShell.java
index 93104b783b1424564fcd05e964acd50e5a830147..2d54f99f4288e11a1a1f9739f948046b2c200602 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShell.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShell.java
@@ -29,6 +29,7 @@ import com.google.vr.ndk.base.GvrLayout;
 
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.base.annotations.UsedByReflection;
 import org.chromium.chrome.browser.ChromeVersionInfo;
 import org.chromium.chrome.browser.WebContentsFactory;
 import org.chromium.chrome.browser.tab.Tab;
@@ -45,9 +46,11 @@ import javax.microedition.khronos.opengles.GL10;
  * This view extends from GvrLayout which wraps a GLSurfaceView that renders VR shell.
  */
 @JNINamespace("vr_shell")
+@UsedByReflection("VrShellDelegate.java")
 public class VrShell extends GvrLayout implements GLSurfaceView.Renderer, VrShellInterface {
     private static final String TAG = "VrShell";
 
+    @UsedByReflection("VrShellDelegate.java")
     public static final String VR_EXTRA = com.google.vr.sdk.base.Constants.EXTRA_VR_LAUNCH;
 
     private Activity mActivity;
@@ -94,6 +97,7 @@ public class VrShell extends GvrLayout implements GLSurfaceView.Renderer, VrShel
         }
     }
 
+    @UsedByReflection("VrShellDelegate.java")
     public VrShell(Activity activity) {
         super(activity);
         mActivity = activity;