Fix NFC test not working in WebappActivity

Fixes the issue of CCT/WAA NFC tests getting stuck in the DOFF flow.
This was somehow caused by the webpage listening for vrdisplayactivate,
but not actually presenting with it.

Also adds a sleep at the end of the test to prevent a possible race
condition with VrCore's 2 second NFC debounce timeout.

Bug: 787878
Change-Id: Ic5f16258cfa94ce3fac63781c1e225b8b2749f4e
Reviewed-on: https://chromium-review.googlesource.com/791938
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#519499}

chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/WebVrTransitionTest.java

@@ -13,6 +13,8 @@ import static org.chromium.chrome.test.util.ChromeRestriction.RESTRICTION_TYPE_V
 
 import android.app.Activity;
 import android.os.Build;
+import android.os.SystemClock;
+import android.support.test.filters.LargeTest;
 import android.support.test.filters.MediumTest;
 
 import org.junit.Assert;
@@ -114,13 +116,12 @@ public class WebVrTransitionTest {
 
     /**
      * Tests that scanning the Daydream View NFC tag on supported devices fires the
-     * vrdisplayactivate event.
+     * vrdisplayactivate event and the event allows presentation without a user gesture.
      */
     @Test
-    @MediumTest
+    @LargeTest
     @Restriction(RESTRICTION_TYPE_VIEWER_DAYDREAM)
-    @VrActivityRestriction({VrActivityRestriction.SupportedActivity.CTA,
-            VrActivityRestriction.SupportedActivity.CCT})
+    @VrActivityRestriction({VrActivityRestriction.SupportedActivity.ALL})
     public void testNfcFiresVrdisplayactivate() throws InterruptedException {
         mVrTestFramework.loadUrlAndAwaitInitialization(
                 VrTestFramework.getHtmlTestFile("test_nfc_fires_vrdisplayactivate"),
@@ -130,6 +131,11 @@ public class WebVrTransitionTest {
         NfcSimUtils.simNfcScan(mVrTestRule.getActivity());
         VrTestFramework.waitOnJavaScriptStep(mVrTestFramework.getFirstTabWebContents());
         VrTestFramework.endTest(mVrTestFramework.getFirstTabWebContents());
+        // VrCore has a 2000 ms debounce timeout on NFC scans. When run multiple times in different
+        // activities, it is possible for a latter test to be run in the 2 seconds after the
+        // previous test's NFC scan, causing it to fail flakily. So, wait 2 seconds to ensure that
+        // can't happen.
+        SystemClock.sleep(2000);
     }
 
     /**

chrome/test/data/android/webvr_instrumentation/html/test_nfc_fires_vrdisplayactivate.html

@@ -11,10 +11,20 @@ vrdisplayactivate event
     <canvas id="webgl-canvas"></canvas>
     <script src="../../../../../../third_party/WebKit/LayoutTests/resources/testharness.js"></script>
     <script src="../resources/webvr_e2e.js"></script>
+    <script src="../resources/webvr_boilerplate.js"></script>
     <script>
       var t = async_test("NFC scan fires the vrdisplayactivate event");
       function addListener() {
-        window.addEventListener("vrdisplayactivate", () => {t.done();}, false);
+        window.addEventListener("vrdisplayactivate", () => {
+          vrDisplay.requestPresent([{source: webglCanvas}]).then( () => {
+            // Do nothing
+          }, (err) => {
+            t.step( () => {
+              assert_unreached(
+                  "Was unable to present with vrdisplayactivate: " + err);
+            });
+          }).then( () => {t.done()});
+        }, false);
       }
       // NFC scan triggered after page loaded and listener added
     </script>