Refactored how WebRTC content browser tests talk to their javascript.

We will now use the domAutomationController rather than looking at the
page title. This will confer the following advantages:

- Tests will fail right away when the js detects an error, rather than
  timing out.
- We will get a lot better stack traces when errors do occur.
- The communication path to the tests becomes more flexible with
  possibility for custom return values (for instance if we need to
  verify something in the C++ code or have a multi-stage test).

BUG=None
NOTRY=True

(doing notry since CQ gets stuck on telemetry test on mac_rel)

Review URL: https://codereview.chromium.org/190563002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255795 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/media/webrtc_aecdump_browsertest.cc

@@ -67,12 +67,12 @@ IN_PROC_BROWSER_TEST_F(WebRtcAecDumpBrowserTest, MAYBE_CallWithAecDump) {
   NavigateToURL(shell(), url);
 
 #if defined (OS_ANDROID)
-    // Always force iSAC 16K on Android for now (Opus is broken).
-    ASSERT_TRUE(ExecuteJavascript("forceIsac16KInSdp();"));
+  // Always force iSAC 16K on Android for now (Opus is broken).
+  EXPECT_EQ("isac-forced",
+            ExecuteJavascriptAndReturnResult("forceIsac16KInSdp();"));
 #endif
 
-  EXPECT_TRUE(ExecuteJavascript("call({video: true, audio: true});"));
-  ExpectTitle("OK");
+  ExecuteJavascriptAndWaitForOk("call({video: true, audio: true});");
 
   EXPECT_TRUE(base::PathExists(dump_file_));
   int64 file_size = 0;

content/browser/media/webrtc_browsertest.cc

@@ -34,17 +34,17 @@ class WebRtcBrowserTest : public WebRtcContentBrowserTest {
 
     GURL url(embedded_test_server()->GetURL("/media/peerconnection-call.html"));
     NavigateToURL(shell(), url);
-    ExecuteTestAndWaitForOk(javascript);
+
+    DisableOpusIfOnAndroid();
+    ExecuteJavascriptAndWaitForOk(javascript);
   }
 
-  void ExecuteTestAndWaitForOk(const std::string& javascript) {
+  void DisableOpusIfOnAndroid() {
 #if defined (OS_ANDROID)
     // Always force iSAC 16K on Android for now (Opus is broken).
-    ASSERT_TRUE(ExecuteJavascript("forceIsac16KInSdp();"));
+    EXPECT_EQ("isac-forced",
+              ExecuteJavascriptAndReturnResult("forceIsac16KInSdp();"));
 #endif
-
-    ASSERT_TRUE(ExecuteJavascript(javascript));
-    ExpectTitle("OK");
   }
 };
 
@@ -331,7 +331,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcBrowserTest, MAYBE_CallWithAecDump) {
 
   GURL url(embedded_test_server()->GetURL("/media/peerconnection-call.html"));
   NavigateToURL(shell(), url);
-  ExecuteTestAndWaitForOk("call({video: true, audio: true});");
+  DisableOpusIfOnAndroid();
+  ExecuteJavascriptAndWaitForOk("call({video: true, audio: true});");
 
   EXPECT_TRUE(base::PathExists(dump_file));
   int64 file_size = 0;
@@ -367,7 +368,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcBrowserTest,
 
   GURL url(embedded_test_server()->GetURL("/media/peerconnection-call.html"));
   NavigateToURL(shell(), url);
-  ExecuteTestAndWaitForOk("call({video: true, audio: true});");
+  DisableOpusIfOnAndroid();
+  ExecuteJavascriptAndWaitForOk("call({video: true, audio: true});");
 
   EXPECT_TRUE(base::PathExists(dump_file));
   int64 file_size = 0;

content/browser/media/webrtc_getusermedia_browsertest.cc

@@ -28,14 +28,14 @@ using trace_analyzer::TraceEventVector;
 namespace {
 
 static const char kGetUserMediaAndStop[] = "getUserMediaAndStop";
-static const char kGetUserMediaAndWaitAndStop[] = "getUserMediaAndWaitAndStop";
+static const char kGetUserMediaAndGetStreamUp[] = "getUserMediaAndGetStreamUp";
 static const char kGetUserMediaAndAnalyseAndStop[] =
     "getUserMediaAndAnalyseAndStop";
+static const char kGetUserMediaAndExpectFailure[] =
+    "getUserMediaAndExpectFailure";
 
 // Results returned by JS.
 static const char kOK[] = "OK";
-static const char kGetUserMediaFailed[] =
-    "GetUserMedia call failed with code undefined";
 
 std::string GenerateGetUserMediaWithMandatorySourceID(
     const std::string& function_name,
@@ -109,20 +109,23 @@ class WebRtcGetUserMediaBrowserTest: public WebRtcContentBrowserTest {
 
     GURL url(embedded_test_server()->GetURL("/media/getusermedia.html"));
     NavigateToURL(shell(), url);
+
     // Put getUserMedia to work and let it run for a couple of seconds.
     DCHECK(time_to_sample_secs);
-    ASSERT_TRUE(
-        ExecuteJavascript(base::StringPrintf("%s({video: true}, %d);",
-                                             kGetUserMediaAndWaitAndStop,
-                                             time_to_sample_secs)));
+    ASSERT_EQ("ok-stream-running",
+        ExecuteJavascriptAndReturnResult(
+            base::StringPrintf("%s({video: true});",
+                               kGetUserMediaAndGetStreamUp)));
 
-    // Make sure the stream is up and running, then start collecting traces.
-    ExpectTitle("Running...");
+    // Now the stream is up and running, start collecting traces.
     StartTracing();
 
+    // Let the stream run for a while in javascript.
+    ExecuteJavascriptAndWaitForOk(
+        base::StringPrintf("waitAndStopVideoTrack(%d);", time_to_sample_secs));
+
     // Wait until the page title changes to "OK". Do not sleep() here since that
     // would stop both this code and the browser underneath.
-    ExpectTitle("OK");
     StopTracing();
 
     scoped_ptr<TraceAnalyzer> analyzer(CreateTraceAnalyzer());
@@ -214,10 +217,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest, GetVideoStreamAndStop) {
   GURL url(embedded_test_server()->GetURL("/media/getusermedia.html"));
   NavigateToURL(shell(), url);
 
-  ASSERT_TRUE(ExecuteJavascript(
-      base::StringPrintf("%s({video: true});", kGetUserMediaAndStop)));
-
-  ExpectTitle("OK");
+  ExecuteJavascriptAndWaitForOk(
+      base::StringPrintf("%s({video: true});", kGetUserMediaAndStop));
 }
 
 IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
@@ -227,10 +228,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
   GURL url(embedded_test_server()->GetURL("/media/getusermedia.html"));
   NavigateToURL(shell(), url);
 
-  ASSERT_TRUE(ExecuteJavascript(base::StringPrintf(
-      "%s({video: true, audio: true});", kGetUserMediaAndStop)));
-
-  ExpectTitle("OK");
+  ExecuteJavascriptAndWaitForOk(base::StringPrintf(
+      "%s({video: true, audio: true});", kGetUserMediaAndStop));
 }
 
 IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
@@ -240,9 +239,7 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
   GURL url(embedded_test_server()->GetURL("/media/getusermedia.html"));
   NavigateToURL(shell(), url);
 
-  ASSERT_TRUE(ExecuteJavascript("getUserMediaAndClone();"));
-
-  ExpectTitle("OK");
+  ExecuteJavascriptAndWaitForOk("getUserMediaAndClone();");
 }
 
 IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
@@ -282,25 +279,25 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
 
   // Test with invalid mandatory audio sourceID.
   NavigateToURL(shell(), url);
-  EXPECT_EQ(kGetUserMediaFailed, ExecuteJavascriptAndReturnResult(
+  ExecuteJavascriptAndWaitForOk(
       GenerateGetUserMediaWithMandatorySourceID(
-          kGetUserMediaAndStop,
+          kGetUserMediaAndExpectFailure,
           "something invalid",
-          video_ids[0])));
+          video_ids[0]));
 
   // Test with invalid mandatory video sourceID.
-  EXPECT_EQ(kGetUserMediaFailed, ExecuteJavascriptAndReturnResult(
+  ExecuteJavascriptAndWaitForOk(
       GenerateGetUserMediaWithMandatorySourceID(
-          kGetUserMediaAndStop,
+          kGetUserMediaAndExpectFailure,
           audio_ids[0],
-          "something invalid")));
+          "something invalid"));
 
   // Test with empty mandatory audio sourceID.
-  EXPECT_EQ(kGetUserMediaFailed, ExecuteJavascriptAndReturnResult(
+  ExecuteJavascriptAndWaitForOk(
       GenerateGetUserMediaWithMandatorySourceID(
-          kGetUserMediaAndStop,
+          kGetUserMediaAndExpectFailure,
           "",
-          video_ids[0])));
+          video_ids[0]));
 }
 
 IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
@@ -342,10 +339,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest, TwoGetUserMediaAndStop) {
   GURL url(embedded_test_server()->GetURL("/media/getusermedia.html"));
   NavigateToURL(shell(), url);
 
-  ASSERT_TRUE(ExecuteJavascript(
-      "twoGetUserMediaAndStop({video: true, audio: true});"));
-
-  ExpectTitle("OK");
+  ExecuteJavascriptAndWaitForOk(
+      "twoGetUserMediaAndStop({video: true, audio: true});");
 }
 
 // This test will make a simple getUserMedia page, verify that video is playing
@@ -388,8 +383,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
   // TODO(mcasas): add more aspect ratios, in particular 16:10 crbug.com/275594.
 
   NavigateToURL(shell(), url);
-  ASSERT_TRUE(ExecuteJavascript(constraints_4_3));
-  ExpectTitle("4:3 letterbox");
+  ASSERT_EQ("4:3 letterbox",
+            ExecuteJavascriptAndReturnResult(constraints_4_3));
 }
 
 // This test calls getUserMedia and checks for aspect ratio behavior.
@@ -406,8 +401,8 @@ IN_PROC_BROWSER_TEST_F(WebRtcGetUserMediaBrowserTest,
       kGetUserMediaAndAnalyseAndStop, 640, 640, 360, 360, 30, 30);
 
   NavigateToURL(shell(), url);
-  ASSERT_TRUE(ExecuteJavascript(constraints_16_9));
-  ExpectTitle("16:9 letterbox");
+  ASSERT_EQ("16:9 letterbox",
+            ExecuteJavascriptAndReturnResult(constraints_16_9));
 }
 
 namespace {
@@ -449,8 +444,7 @@ IN_PROC_BROWSER_TEST_P(WebRtcConstraintsBrowserTest, GetUserMediaConstraints) {
                                               user_media().max_frame_rate);
   DVLOG(1) << "Calling getUserMedia: " << call;
   NavigateToURL(shell(), url);
-  ASSERT_TRUE(ExecuteJavascript(call));
-  ExpectTitle("OK");
+  ExecuteJavascriptAndWaitForOk(call);
 }
 
 static const UserMediaSizes kAllUserMediaSizes[] = {

content/test/data/media/getusermedia.html

@@ -10,15 +10,9 @@
 
   setAllEventsOccuredHandler(function() {
     gLocalStream.stop();
-    document.title = 'OK';
-    sendValueToTest(document.title);
+    reportTestSuccess();
   });
 
-  function sendValueToTest(value) {
-    window.domAutomationController.setAutomationId(0);
-    window.domAutomationController.send(value);
-  }
-
   function getSources() {
     MediaStreamTrack.getSources(function(devices) {
       document.title = 'Sources Available';
@@ -29,30 +23,42 @@
   // Creates a MediaStream and renders it locally. When the video is detected to
   // be rolling, the title is changed and the stream should be stopped.
   function getUserMediaAndStop(constraints) {
-    document.title = 'Calling GetUserMedia';
+    console.log('Calling getUserMediaAndStop.');
     navigator.webkitGetUserMedia(
         constraints,
         function(stream) { displayAndDetectVideo(stream, stopVideoTrack); },
         failedCallback);
   }
 
+  // Requests getusermedia and expects it to fail.
+  function getUserMediaAndExpectFailure(constraints) {
+    console.log('Calling getUserMediaAndExpectFailure.');
+    navigator.webkitGetUserMedia(
+        constraints,
+        function(stream) { failTest('Unexpectedly succeeded getUserMedia.'); },
+        function(error) { reportTestSuccess(); });
+  }
+
   // Creates a MediaStream and renders it locally. When the video is detected to
-  // be rolling, the title should be changed and the stream is let roll for a
-  // number |waitTimeInSeconds| and then it should be stopped.
-  function getUserMediaAndWaitAndStop(constraints, waitTimeInSeconds) {
+  // be rolling we return ok-stream-running through the automation controller.
+  function getUserMediaAndGetStreamUp(constraints, waitTimeInSeconds) {
+    console.log('Calling getUserMediaAndGetStreamUp.');
     navigator.webkitGetUserMedia(
         constraints,
         function(stream) {
           displayAndDetectVideo(
             stream,
             function() {
-              waitAndStopVideoTrack(waitTimeInSeconds);
+              sendValueToTest('ok-stream-running');
             });
         },
         failedCallback);
   }
 
+  // Gets a video stream up, analyses it and returns the aspect ratio to the
+  // test through the automation controller.
   function getUserMediaAndAnalyseAndStop(constraints) {
+    console.log('Calling getUserMediaAndAnalyseAndStop.');
     navigator.webkitGetUserMedia(
         constraints, displayDetectAndAnalyzeVideo, failedCallback);
   }
@@ -60,6 +66,7 @@
   // This test that a MediaStream can be cloned and that the clone can
   // be rendered.
   function getUserMediaAndClone() {
+    console.log('Calling getUserMediaAndClone.');
     navigator.webkitGetUserMedia({video: true, audio: true},
         createAndRenderClone, failedCallback);
   }
@@ -69,36 +76,35 @@
   // streams have the same source, both video streams should stop. If they do,
   // the test succeeds.
   function twoGetUserMediaAndStop(constraints) {
-    document.title = 'Calling Two GetUserMedia';
+    console.log('Calling Two GetUserMedia');
     navigator.webkitGetUserMedia(
         constraints,
-        function(stream) { 
-          displayAndDetectVideo(stream, requestSecondGetUserMedia); 
+        function(stream) {
+          displayAndDetectVideo(stream, requestSecondGetUserMedia);
         },
         failedCallback);
     var requestSecondGetUserMedia = function() {
       navigator.webkitGetUserMedia(
           constraints,
-          function(stream) { 
-            displayIntoVideoElement(stream, 
+          function(stream) {
+            displayIntoVideoElement(stream,
                 stopStreamAndVerifyAllLocalViewsDontPlayVideo, 'local-view-2');
           },
           failedCallback);
     };
-    
+
     var stopStreamAndVerifyAllLocalViewsDontPlayVideo = function() {
       gLocalStream.getVideoTracks()[0].stop();
-      
+
       // Since local-view and local-view-2 are playing the video from the same
       // source, both of them should stop.
       waitForVideoToStop('local-view');
       waitForVideoToStop('local-view-2');
-    };   
+    };
   }
 
   function failedCallback(error) {
-    document.title = 'GetUserMedia call failed with code ' + error.code;
-    sendValueToTest(document.title);
+    failTest('GetUserMedia call failed with code ' + error.code);
   }
 
   function plugStreamIntoVideoElement(stream, videoElement) {
@@ -109,7 +115,6 @@
 
   function displayIntoVideoElement(stream, callback, videoElement) {
     plugStreamIntoVideoElement(stream, videoElement);
-    document.title = 'Waiting for video...';
     detectVideoPlaying(videoElement, callback);
   }
 
@@ -128,12 +133,12 @@
     // work with audio devices and not all bots has a microphone.
     new_stream = new webkitMediaStream();
     new_stream.addTrack(stream.getVideoTracks()[0]);
-    expectEquals(new_stream.getVideoTracks().length, 1);
+    assertEquals(new_stream.getVideoTracks().length, 1);
     if (stream.getAudioTracks().length > 0) {
       new_stream.addTrack(stream.getAudioTracks()[0]);
-      expectEquals(new_stream.getAudioTracks().length, 1);
+      assertEquals(new_stream.getAudioTracks().length, 1);
       new_stream.removeTrack(new_stream.getAudioTracks()[0]);
-      expectEquals(new_stream.getAudioTracks().length, 0);
+      assertEquals(new_stream.getAudioTracks().length, 0);
     }
 
     var newStreamUrl = URL.createObjectURL(new_stream);
@@ -147,19 +152,102 @@
   }
 
   function waitAndStopVideoTrack(waitTimeInSeconds) {
-    document.title = 'Running...';
     setTimeout(stopVideoTrack, waitTimeInSeconds * 1000);
   }
 
   function analyzeVideo() {
-    document.title = 'Waiting for video...';
-    addExpectedEvent();
     detectAspectRatio(function(aspectRatio) {
-      document.title = aspectRatio;
-      eventOccured();
+      sendValueToTest(aspectRatio);
     });
   }
 
+  // This function tries to calculate the aspect ratio shown by the fake capture
+  // device in the video tag. For this, we count the amount of light green
+  // pixels along |aperture| pixels on the positive X and Y axis starting from
+  // the center of the image. In this very center there should be a time-varying
+  // pacman; the algorithm counts for a couple of iterations and keeps the
+  // maximum amount of light green pixels on both directions. From this data
+  // the aspect ratio is calculated relative to a 320x240 window, so 4:3 would
+  // show as a 1. Furthermore, since an original non-4:3 might be letterboxed or
+  // cropped, the actual X and Y pixel amounts are compared with the fake video
+  // capture expected pacman radius (see further below).
+  function detectAspectRatio(callback) {
+    var width = VIDEO_TAG_WIDTH;
+    var height = VIDEO_TAG_HEIGHT;
+    var videoElement = $('local-view');
+    var canvas = $('local-view-canvas');
+
+    var maxLightGreenPixelsX = 0;
+    var maxLightGreenPixelsY = 0;
+
+    var aperture = Math.min(width, height) / 2;
+    var iterations = 0;
+    var maxIterations = 10;
+
+    var detectorFunction = function() {
+      var context = canvas.getContext('2d');
+      context.drawImage(videoElement, 0, 0, width, height);
+
+      // We are interested in a window starting from the center of the image
+      // where we expect the circle from the fake video capture to be rolling.
+      var pixels = context.getImageData(width / 2, height / 2,
+                                        aperture, aperture);
+
+      var lightGreenPixelsX = 0;
+      var lightGreenPixelsY = 0;
+
+      // Walk horizontally counting light green pixels.
+      for (var x = 0; x < aperture; ++x) {
+        if (pixels.data[4 * x + 1] != COLOR_BACKGROUND_GREEN)
+          lightGreenPixelsX++;
+      }
+      // Walk vertically counting light green pixels.
+      for (var y = 0; y < aperture; ++y) {
+        if (pixels.data[4 * y * aperture + 1] != 135)
+          lightGreenPixelsY++;
+      }
+      if (lightGreenPixelsX > maxLightGreenPixelsX &&
+          lightGreenPixelsX < aperture)
+        maxLightGreenPixelsX = lightGreenPixelsX;
+      if (lightGreenPixelsY > maxLightGreenPixelsY &&
+          lightGreenPixelsY < aperture)
+        maxLightGreenPixelsY = lightGreenPixelsY;
+
+      var detectedAspectRatioString = "";
+      if (++iterations > maxIterations) {
+        clearInterval(detectorFunction);
+        observedAspectRatio = maxLightGreenPixelsY / maxLightGreenPixelsX;
+        // At this point the observed aspect ratio is either 1, for undistorted
+        // 4:3, or some other aspect ratio that is seen as distorted.
+        if (Math.abs(observedAspectRatio - 1.333) < 0.1)
+          detectedAspectRatioString = "16:9";
+        else if (Math.abs(observedAspectRatio - 1.20) < 0.1)
+          detectedAspectRatioString = "16:10";
+        else if (Math.abs(observedAspectRatio - 1.0) < 0.1)
+          detectedAspectRatioString = "4:3";
+        else
+          detectedAspectRatioString = "UNKNOWN aspect ratio";
+        console.log(detectedAspectRatioString + " observed aspect ratio (" +
+                    observedAspectRatio + ")");
+
+        // The FakeVideoCapture calculates the circle radius as
+        // std::min(capture_format_.width, capture_format_.height) / 4;
+        // we do the same and see if both dimensions are scaled, meaning
+        // we started from a cropped or stretched image.
+        var nonDistortedRadius = Math.min(width, height) / 4;
+        if ((maxLightGreenPixelsX != nonDistortedRadius) &&
+            (maxLightGreenPixelsY != nonDistortedRadius)) {
+          detectedAspectRatioString += " cropped";
+        } else
+          detectedAspectRatioString += " letterbox";
+
+        console.log("Original image is: " + detectedAspectRatioString);
+        callback(detectedAspectRatioString);
+      }
+    }
+
+    setInterval(detectorFunction, 50);
+  }
   </script>
 </head>
 <body>

content/test/data/media/webrtc_test_audio.js

@@ -70,7 +70,7 @@ function getAudioLevelFromStats_(response) {
     }
   }
   // Should only be one audio level reported, otherwise we get confused.
-  expectEquals(1, audioOutputLevels.length);
+  assertEquals(1, audioOutputLevels.length);
 
   return audioOutputLevels[0];
 }

content/test/data/media/webrtc_test_utilities.js

@@ -24,6 +24,23 @@ function setAllEventsOccuredHandler(handler) {
   gAllEventsOccured = handler;
 }
 
+// Tells the C++ code we succeeded, which will generally exit the test.
+function reportTestSuccess() {
+  window.domAutomationController.send('OK');
+}
+
+// Returns a custom return value to the test.
+function sendValueToTest(value) {
+  window.domAutomationController.send(value);
+}
+
+// Immediately fails the test on the C++ side and throw an exception to
+// stop execution on the javascript side.
+function failTest(reason) {
+  var error = new Error(reason);
+  window.domAutomationController.send(error.stack);
+}
+
 function detectVideoPlaying(videoElementName, callback) {
   detectVideo(videoElementName, isVideoPlaying, callback);
 }
@@ -62,13 +79,11 @@ function detectVideo(videoElementName, predicate, callback) {
 }
 
 function waitForVideo(videoElement) {
-  document.title = 'Waiting for video...';
   addExpectedEvent();
   detectVideoPlaying(videoElement, function () { eventOccured(); });
 }
 
 function waitForVideoToStop(videoElement) {
-  document.title = 'Waiting for video to stop...';
   addExpectedEvent();
   detectVideoStopped(videoElement, function () { eventOccured(); });
 }
@@ -82,10 +97,15 @@ function waitForConnectionToStabilize(peerConnection, callback) {
   }, 100);
 }
 
+// Adds an expected event. You may call this function many times to add more
+// expected events. Each expected event must later be matched by a call to
+// eventOccurred. When enough events have occurred, the "all events occurred
+// handler" will be called.
 function addExpectedEvent() {
   ++gNumberOfExpectedEvents;
 }
 
+// See addExpectedEvent.
 function eventOccured() {
   ++gNumberOfEvents;
   if (gNumberOfEvents == gNumberOfExpectedEvents) {
@@ -104,99 +124,11 @@ function isVideoPlaying(pixels, previousPixels) {
   return false;
 }
 
-// This function matches |left| and |right| and throws an exception if the
-// values don't match.
-function expectEquals(left, right) {
-  if (left != right) {
-    var s = "expectEquals failed left: " + left + " right: " + right;
-    document.title = s;
-    throw s;
+// This function matches |left| and |right| and fails the test if the
+// values don't match using normal javascript equality (i.e. the hard
+// types of the operands aren't checked).
+function assertEquals(expected, actual) {
+  if (actual != expected) {
+    failTest("expected '" + expected + "', got '" + actual + "'.");
   }
 }
-
-// This function tries to calculate the aspect ratio shown by the fake capture
-// device in the video tag. For this, we count the amount of light green pixels
-// along |aperture| pixels on the positive X and Y axis starting from the
-// center of the image. In this very center there should be a time-varying
-// pacman; the algorithm counts for a couple of iterations and keeps the
-// maximum amount of light green pixels on both directions. From this data
-// the aspect ratio is calculated relative to a 320x240 window, so 4:3 would
-// show as a 1. Furthermore, since an original non-4:3 might be letterboxed or
-// cropped, the actual X and Y pixel amounts are compared with the fake video
-// capture expected pacman radius (see further below).
-function detectAspectRatio(callback) {
-  var width = VIDEO_TAG_WIDTH;
-  var height = VIDEO_TAG_HEIGHT;
-  var videoElement = $('local-view');
-  var canvas = $('local-view-canvas');
-
-  var maxLightGreenPixelsX = 0;
-  var maxLightGreenPixelsY = 0;
-
-  var aperture = Math.min(width, height) / 2;
-  var iterations = 0;
-  var maxIterations = 10;
-
-  var waitVideo = setInterval(function() {
-    var context = canvas.getContext('2d');
-    context.drawImage(videoElement, 0, 0, width, height);
-
-    // We are interested in a window starting from the center of the image
-    // where we expect the circle from the fake video capture to be rolling.
-    var pixels =
-        context.getImageData(width / 2, height / 2, aperture, aperture);
-
-    var lightGreenPixelsX = 0;
-    var lightGreenPixelsY = 0;
-
-    // Walk horizontally counting light green pixels.
-    for (var x = 0; x < aperture; ++x) {
-      if (pixels.data[4 * x + 1] != COLOR_BACKGROUND_GREEN)
-        lightGreenPixelsX++;
-    }
-    // Walk vertically counting light green pixels.
-    for (var y = 0; y < aperture; ++y) {
-      if (pixels.data[4 * y * aperture + 1] != 135)
-        lightGreenPixelsY++;
-    }
-    if (lightGreenPixelsX > maxLightGreenPixelsX &&
-        lightGreenPixelsX < aperture)
-      maxLightGreenPixelsX = lightGreenPixelsX;
-    if (lightGreenPixelsY > maxLightGreenPixelsY &&
-        lightGreenPixelsY < aperture)
-      maxLightGreenPixelsY = lightGreenPixelsY;
-
-    var detectedAspectRatioString = "";
-    if (++iterations > maxIterations) {
-      clearInterval(waitVideo);
-      observedAspectRatio = maxLightGreenPixelsY / maxLightGreenPixelsX;
-      // At this point the observed aspect ratio is either 1, for undistorted
-      // 4:3, or some other aspect ratio that is seen as distorted.
-      if (Math.abs(observedAspectRatio - 1.333) < 0.1)
-        detectedAspectRatioString = "16:9";
-      else if (Math.abs(observedAspectRatio - 1.20) < 0.1)
-        detectedAspectRatioString = "16:10";
-      else if (Math.abs(observedAspectRatio - 1.0) < 0.1)
-        detectedAspectRatioString = "4:3";
-      else
-        detectedAspectRatioString = "UNKNOWN aspect ratio";
-      console.log(detectedAspectRatioString + " observed aspect ratio (" +
-                  observedAspectRatio + ")");
-
-      // The FakeVideoCapture calculates the circle radius as
-      // std::min(capture_format_.width, capture_format_.height) / 4;
-      // we do the same and see if both dimensions are scaled, meaning
-      // we started from a cropped or stretched image.
-      var nonDistortedRadius = Math.min(width, height) / 4;
-      if ((maxLightGreenPixelsX != nonDistortedRadius) &&
-          (maxLightGreenPixelsY != nonDistortedRadius)) {
-        detectedAspectRatioString += " cropped";
-      } else
-        detectedAspectRatioString += " letterbox";
-
-      console.log("Original image is: " + detectedAspectRatioString);
-      callback(detectedAspectRatioString);
-    }
-  },
-                              50);
-}

content/test/webrtc_content_browsertest_base.cc

@@ -33,11 +33,6 @@ void WebRtcContentBrowserTest::SetUp() {
   ContentBrowserTest::SetUp();
 }
 
-bool WebRtcContentBrowserTest::ExecuteJavascript(
-    const std::string& javascript) {
-  return ExecuteScript(shell()->web_contents(), javascript);
-}
-
 // Executes |javascript|. The script is required to use
 // window.domAutomationController.send to send a string value back to here.
 std::string WebRtcContentBrowserTest::ExecuteJavascriptAndReturnResult(
@@ -49,12 +44,14 @@ std::string WebRtcContentBrowserTest::ExecuteJavascriptAndReturnResult(
   return result;
 }
 
-void WebRtcContentBrowserTest::ExpectTitle(
-    const std::string& expected_title) const {
-  base::string16 expected_title16(base::ASCIIToUTF16(expected_title));
-  TitleWatcher title_watcher(shell()->web_contents(), expected_title16);
-  EXPECT_EQ(expected_title16, title_watcher.WaitAndGetTitle());
-}
+void WebRtcContentBrowserTest::ExecuteJavascriptAndWaitForOk(
+    const std::string& javascript) {
+   std::string result = ExecuteJavascriptAndReturnResult(javascript);
+   if (result != "OK") {
+     printf("From javascript: %s", result.c_str());
+     FAIL();
+   }
+ }
 
 std::string WebRtcContentBrowserTest::GenerateGetUserMediaCall(
     const char* function_name,

content/test/webrtc_content_browsertest_base.h

@@ -15,16 +15,14 @@ class WebRtcContentBrowserTest: public ContentBrowserTest {
   virtual void SetUp() OVERRIDE;
 
  protected:
-  // Executes |javascript| and returns after it has been executed.
-  bool ExecuteJavascript(const std::string& javascript);
-
   // Executes |javascript|. The script is required to use
   // window.domAutomationController.send to send a string value back to here.
   std::string ExecuteJavascriptAndReturnResult(
       const std::string& javascript);
 
-  // Waits for the page title to be set to |expected_title|.
-  void ExpectTitle(const std::string& expected_title) const;
+  // Waits for the javascript to return OK via the automation controller.
+  // If the javascript returns != OK or times out, we fail the test.
+  void ExecuteJavascriptAndWaitForOk(const std::string& javascript);
 
   // Generates javascript code for a getUserMedia call.
   std::string GenerateGetUserMediaCall(const char* function_name,