Include viewport visibility checks for autoplay experiment.

third_party/WebKit/LayoutTests/media/video-autoplay-experiment-modes.html

Index: third_party/WebKit/LayoutTests/media/video-autoplay-experiment-modes.html
diff --git a/third_party/WebKit/LayoutTests/media/video-autoplay-experiment-modes.html b/third_party/WebKit/LayoutTests/media/video-autoplay-experiment-modes.html
index 04c704db8ca303cfb73658ac1f48d573b03baccf..f6230f0dc7481ab431704e7326b114b97f83edba 100644
--- a/third_party/WebKit/LayoutTests/media/video-autoplay-experiment-modes.html
+++ b/third_party/WebKit/LayoutTests/media/video-autoplay-experiment-modes.html
@@ -13,10 +13,12 @@
   Flags  - autoplay experiment setting being tested.
                a      - "foraudio"
                v      - "forvideo"
+               V      - "ifviewport"
+               P      - "ifpagevisible"
                M      - "ifmuted"
                p      - "playmuted"
                m      - "ifmobile"
-               For example, EM means "enabled-ifmuted".
+               For example, vM means '-forvideo-ifmuted".
   Type   - audio or video element?
                audio  - <audio>
                video  - <video>
@@ -30,8 +32,16 @@
   Mobile - is page optimized for mobile?
                no   - page is not optimized for mobile.
                yes  - page is optimized for mobile.
+  View   - is media in viewport?
+               onscreen  - element starts out onscreen.
+               scroll    - element starts offscreen, scrolled into view once
+                           it is ready to play.
+               offscreen - element starts out offscreen and stays offscreen.
+               obscured  - onscreen but page is not visible.
 
   == Test Outputs ==
+  Early?  - did playback start before element was scrolled onscreen?  For
+            tests in which View!=scroll, this is reported as "-".
   Played? - did playback start by the conclusion of the test?
   Muted?  - was the media muted?  If the media didn't play, then this is
             reported as "-".
@@ -45,6 +55,8 @@
 <td>Play w/</td>
 <td>Mute</td>
 <td>Mobile</td>
+<td>View</td>
+<td>Early?</td>
 <td>Played?</td>
 <td>Muted?</td>
 </tr>
@@ -58,15 +70,19 @@ var configNumber = 0;
 
 var mediaFile = findMediaFile("video", "content/test");
 var onscreenParent = document.createElement("div");
+// The onscreen parent's height is also used to make sure that the off-screen
+// parent is, in fact, off-screen.
+onscreenParent.style.height = "1000px";
 document.body.insertBefore(onscreenParent, document.body.firstChild);
-// When we remove the meta tag from the document, we put it here.
+// Is the page optimized for mobile?  We can't un-optimize it.
 var isOptimizedForMobile = false;
+// Also create another root that's off the bottom of the window.
+var offscreenParent = document.createElement("div");
+document.body.appendChild(offscreenParent);
 
-function didPlaybackStart(video)
+function didPlaybackStart(element)
 {
-    // We say that the video started if it's not paused or if it played and
-    // already ended.
-    return !video.paused || video.ended;
+    return !element.paused || element.ended;
 }
 
 function becomeOptimizedForMobile(enable)
@@ -101,16 +117,18 @@ function addResultsRow(spec)
     // Process experiment type specially.
     var type = spec.experimentType;
     var smallType = "";
-    smallType += (type.indexOf("-forvideo")>-1)?"v":"";
-    smallType += (type.indexOf("-foraudio")>-1)?"a":"";
-    smallType += (type.indexOf("-ifmuted")>-1)?"M":"";
-    smallType += (type.indexOf("-playmuted")>-1)?"p":"";
-    smallType += (type.indexOf("-ifmobile")>-1)?"m":"";
+    smallType += type.includes("-forvideo")?"v":"";
+    smallType += type.includes("-foraudio")?"a":"";
+    smallType += type.includes("-ifviewport")?"V":"";
+    smallType += type.includes("-ifpagevisible")?"P":"";
+    smallType += type.includes("-ifmuted")?"M":"";
+    smallType += type.includes("-playmuted")?"p":"";
+    smallType += type.includes("-ifmobile")?"m":"";
     row.insertCell().innerText = smallType;
 
     // Add remaining fields.
     var fields = [ "elementType", "autoplayType", "mutedType", "mobileType",
-        "played", "muted"];
+        "visType", "playedEarly", "played", "muted"];
     for(idx in fields)
         row.insertCell().innerText = spec[fields[idx]].substring(0,7);
 }
@@ -137,6 +155,13 @@ function checkElementStatus(element)
     addResultsRow(element.spec);
     element.remove();
 
+    // Scroll back to the top, in case this was a scrolling test.
+    onscreenParent.scrollIntoView();
+
+    // Also make sure that the page is visible again.  Hidden pages cause the
+    // test to proceed very slowly.
+    testRunner.setPageVisibility("visible");
+
     queueNextExperiment();
 }
 
@@ -148,18 +173,30 @@ function runOneConfig(spec)
     var element = document.createElement(spec.elementType);
     element.controls = true;
 
-    onscreenParent.appendChild(element);
+    // Hide or show the page.
+    if (spec.visType == "obscured")
+        testRunner.setPageVisibility("hidden");
+
+    // Pick whether the element will be visible when canPlayThrough.
+    if (spec.visType == "offscreen" || spec.visType == "scroll")
+        offscreenParent.appendChild(element);
+    else
+        onscreenParent.appendChild(element);
 
     // Set any attributes before canPlayThrough.
     if (spec.mutedType == "yes")
         element.muted = true;
     if (spec.autoplayType == "attr")
         element.autoplay = true;
+
     becomeOptimizedForMobile(spec.mobileType == "yes");
 
+    spec.playedEarly = "-";
+
     // Record the spec in the element, so that we can display the
     // results later.
     element.spec = spec;
+    window.internals.triggerAutoplayViewportCheck(element);
 
     // Wait for canplaythrough before continuing, so that the media
     // might actually be playing.
@@ -168,8 +205,23 @@ function runOneConfig(spec)
         // Now that we can play, if we're supposed to play / mute via js do so.
         configureElementViaScript(element, spec);
 
-        // Record the results.
-        checkElementStatus(element);
+        // If we're supposed to scroll the item onscreen after it is ready to
+        // play, then do so now.
+        if(spec.visType == "scroll") {
+            // Record the play state here, too, before we scroll.
+            spec.playedEarly = didPlaybackStart(element) ? "yes" : "no";
+
+            // We are supposed to scroll the player into view.
+            element.scrollIntoView(true);
+            // TODO(liberato): remove once autoplay gesture override experiment concludes.
+            window.internals.triggerAutoplayViewportCheck(element);
+            // Once these two methods return, changes to the element state due
+            // to the autoplay experiment should be observable synchronously.
+            checkElementStatus(element, spec);
+        } else {
+            // Record the results immediately.
+            checkElementStatus(element, spec);
+        }
     });
 
     // Set the source, which will eventually lead to canPlayThrough.
@@ -179,14 +231,18 @@ function runOneConfig(spec)
 var experimentTypes = [
     "none",
     "enabled-forvideo",
-    "enabled-forvideo-ifmuted",
-    "enabled-forvideo-playmuted",
+    "enabled-forvideo-ifpagevisible",
+    "enabled-forvideo-ifviewport",
+    "enabled-forvideo-ifviewport-ifmuted",
+    "enabled-forvideo-ifviewport-playmuted",
     "enabled-foraudio",
     "enabled-forvideo-ifmobile",
+    "enabled-foraudio-ifviewport",
 ];
 var elementTypes = ["video", "audio"];
 var autoplayTypes = ["none", "attr", "play()"];
 var mutedTypes = ["no", "yes"];
+var visTypes = ["onscreen", "scroll", "offscreen", "obscured"];
 // mobileTypes must always start with no, since we cannot un-optimize the page.
 var mobileTypes = ["no", "yes"];
 
@@ -205,6 +261,8 @@ function runNextConfig()
     exp = Math.floor(exp / autoplayTypes.length);
     spec.mutedType = mutedTypes[exp % mutedTypes.length];
     exp = Math.floor(exp / mutedTypes.length);
+    spec.visType = visTypes[exp % visTypes.length];
+    exp = Math.floor(exp / visTypes.length);
     // Mobile must always change last, so that all the "no" cases precede
     // all the "yes" cases, since we can't switch the doc back to "not
     // optimized for mobile".
@@ -220,20 +278,53 @@ function runNextConfig()
 
     // To keep the test fast, skip a few combinations.
     var skip = false;
-    if (spec.experimentType.indexOf("-ifmuted") == -1 && spec.mutedType != "no")
+    if (!spec.experimentType.includes("-ifmuted") && spec.mutedType != "no")
         skip = true;
 
     // Only allow basic combinations for the mobile case.  We just want to
     // test video with autoplay, no mute options when testing -ifmobile.
     // Similarly, if we're setting the page to be optimied for mobile, then
     // require that we're one of those tests.
-    if ((spec.mobileType == "yes" || spec.experimentType.indexOf("-ifmobile")>0)
+    if ((spec.mobileType == "yes" || spec.experimentType.includes("-ifmobile"))
         && (spec.elementType != "video" || spec.autoplayType != "attr"
             || spec.mutedType != "no"
+            || spec.visType != "onscreen"
             || (spec.experimentType != "enabled-forvideo"
                 && spec.experimentType != "enabled-forvideo-ifmobile")))
         skip = true;
 
+    var mismatched =(spec.elementType == "video"
+        && spec.experimentType.includes("-foraudio"))
+        || (spec.elementType == "audio"
+        && spec.experimentType.includes("-forvideo"));
+
+    if (spec.autoplayType == "none" && spec.visType != 'onscreen')
+        skip = true;
+    else if (spec.experimentType.includes("-ifmuted")
+        && spec.visType != "onscreen")
+        skip = true;
+    else if (spec.visType == "offscreen"
+        && spec.autoplayType != "attr")
+        skip = true;
+    else if (!spec.experimentType.includes("-ifmuted")
+        && spec.mutedType == "yes")
+        skip = true;
+    else if (spec.elementType == "audio" && spec.mutedType == "yes")
+        skip = true;
+    else if (spec.elementType == "audio" && spec.visType != "scroll")
+        skip = true;
+    else if (mismatched && spec.visType !="onscreen")
+        skip = true;
+    else if (mismatched && spec.autoplayType != "attr")
+        skip = true;
+    else if (spec.visType == "obscured"
+        && !spec.experimentType.includes("-ifpagevisible"))
+        skip = true;
+    else if ((spec.visType == "offscreen" || spec.visType == "scroll"
+        || spec.autoplayType != "attr" || spec.elementType != "video")
+        && spec.experimentType.includes("-ifpagevisible"))
+        skip = true;
+
     if (skip)
         queueNextExperiment();
     else