Enable WebVR from WebappActivity

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

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
index fc2dfc5e207677ec2afb5945c2435edbb3f7979f..58a27fe703a153672be61971668f5fbd058b068c 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellDelegate.java
@@ -44,6 +44,7 @@ import org.chromium.chrome.browser.infobar.SimpleConfirmInfoBarBuilder;
 import org.chromium.chrome.browser.multiwindow.MultiWindowUtils;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
+import org.chromium.chrome.browser.webapps.WebappActivity;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -278,7 +279,8 @@ public class VrShellDelegate implements ApplicationStatus.ActivityStateListener,
     }
 
     private static boolean activitySupportsPresentation(Activity activity) {
-        return activity instanceof ChromeTabbedActivity || activity instanceof CustomTabActivity;
+        return activity instanceof ChromeTabbedActivity || activity instanceof CustomTabActivity
+                || activity instanceof WebappActivity;
     }
 
     private static boolean activitySupportsVrBrowsing(Activity activity) {