Backed out changeset db3c2a88f79c (bug 1502927) for mochitest failures on test_reduce_time_precision.

dom/media/DOMMediaStream.cpp

@@ -32,10 +32,23 @@
 #include "nsRFPService.h"
 #include "nsServiceManagerUtils.h"
 
+// GetCurrentTime is defined in winbase.h as zero argument macro forwarding to
+// GetTickCount() and conflicts with NS_DECL_NSIDOMMEDIASTREAM, containing
+// currentTime getter.
+#ifdef GetCurrentTime
+#undef GetCurrentTime
+#endif
+
 #ifdef LOG
 #undef LOG
 #endif
 
+// GetCurrentTime is defined in winbase.h as zero argument macro forwarding to
+// GetTickCount() and conflicts with MediaStream::GetCurrentTime.
+#ifdef GetCurrentTime
+#undef GetCurrentTime
+#endif
+
 using namespace mozilla;
 using namespace mozilla::dom;
 using namespace mozilla::layers;
@@ -401,9 +414,9 @@ NS_INTERFACE_MAP_END_INHERITING(DOMMediaStream)
 
 DOMMediaStream::DOMMediaStream(nsPIDOMWindowInner* aWindow,
                                MediaStreamTrackSourceGetter* aTrackSourceGetter)
-  : mWindow(aWindow), mInputStream(nullptr), mOwnedStream(nullptr),
-    mPlaybackStream(nullptr), mTracksPendingRemoval(0),
-    mTrackSourceGetter(aTrackSourceGetter),
+  : mLogicalStreamStartTime(0), mWindow(aWindow),
+    mInputStream(nullptr), mOwnedStream(nullptr), mPlaybackStream(nullptr),
+    mTracksPendingRemoval(0), mTrackSourceGetter(aTrackSourceGetter),
     mPlaybackTrackListener(MakeAndAddRef<PlaybackTrackListener>(this)),
     mTracksCreated(false), mNotifiedOfMediaStreamGraphShutdown(false),
     mActive(false), mSetInactiveOnFinish(false), mCORSMode(CORS_NONE)
@@ -552,6 +565,20 @@ DOMMediaStream::Constructor(const GlobalObject& aGlobal,
   return newStream.forget();
 }
 
+double
+DOMMediaStream::CurrentTime()
+{
+  if (!mPlaybackStream) {
+    return 0.0;
+  }
+  // The value of a MediaStream's CurrentTime will always advance forward; it will never
+  // reset (even if one rewinds a video.) Therefore we can use a single Random Seed
+  // initialized at the same time as the object.
+  return nsRFPService::ReduceTimePrecisionAsSecs(mPlaybackStream->
+    StreamTimeToSeconds(mPlaybackStream->GetCurrentTime() - mLogicalStreamStartTime),
+    GetRandomTimelineSeed());
+}
+
 already_AddRefed<Promise>
 DOMMediaStream::CountUnderlyingStreams(const GlobalObject& aGlobal, ErrorResult& aRv)
 {

dom/media/DOMMediaStream.h

@@ -19,6 +19,12 @@
 #include "mozilla/RelativeTimeline.h"
 #include "PrincipalChangeObserver.h"
 
+// X11 has a #define for CurrentTime. Unbelievable :-(.
+// See dom/media/webaudio/AudioContext.h for more fun!
+#ifdef CurrentTime
+#undef CurrentTime
+#endif
+
 namespace mozilla {
 
 class AbstractThread;
@@ -351,6 +357,8 @@ public:
               const dom::Sequence<OwningNonNull<MediaStreamTrack>>& aTracks,
               ErrorResult& aRv);
 
+  double CurrentTime();
+
   static already_AddRefed<dom::Promise>
   CountUnderlyingStreams(const dom::GlobalObject& aGlobal, ErrorResult& aRv);
 
@@ -514,6 +522,11 @@ public:
                                   nsIPrincipal* aPrincipal,
                                   MediaStreamGraph* aGraph);
 
+  void SetLogicalStreamStartTime(StreamTime aTime)
+  {
+    mLogicalStreamStartTime = aTime;
+  }
+
   /**
    * Adds a MediaStreamTrack to mTracks and raises "addtrack".
    *
@@ -649,6 +662,9 @@ protected:
   // the principal changes.
   void RecomputePrincipal();
 
+  // StreamTime at which the currentTime attribute would return 0.
+  StreamTime mLogicalStreamStartTime;
+
   // We need this to track our parent object.
   nsCOMPtr<nsPIDOMWindowInner> mWindow;
 

dom/media/MediaManager.cpp

@@ -1312,6 +1312,10 @@ public:
         return;
       }
 
+      // Start currentTime from the point where this stream was successfully
+      // returned.
+      aStream->SetLogicalStreamStartTime(aStream->GetPlaybackStream()->GetCurrentTime());
+
       // This is safe since we're on main-thread, and the windowlist can only
       // be invalidated from the main-thread (see OnNavigation)
       LOG(("Returning success for getUserMedia()"));

dom/media/PeerConnection.js

@@ -1221,6 +1221,9 @@ class RTCPeerConnection {
   }
 
   addTrack(track, stream) {
+    if (stream.currentTime === undefined) {
+      throw new this._win.DOMException("invalid stream.", "InvalidParameterError");
+    }
     this._checkClosed();
 
     if (this._transceivers.some(

dom/media/test/test_streams_element_capture.html

@@ -38,6 +38,7 @@ function startTest(test) {
   var stream;
 
   var checkEnded = function() {
+    is(stream.currentTime, vout.currentTime, test.name + " stream final currentTime");
     if (test.duration) {
       isGreaterThanOrEqualEps(vout.currentTime, test.duration,
          test.name + " current time at end");
@@ -57,6 +58,7 @@ function startTest(test) {
 
   var onloadedmetadata = function (ev) {
     stream = v.mozCaptureStreamUntilEnded();
+    is(stream.currentTime, 0, test.name + " stream initial currentTime");
     vout.srcObject = stream;
     is(vout.srcObject, stream, test.name + " set output element .srcObject correctly");
     v.play();

dom/media/tests/mochitest/mediaStreamPlayback.js

@@ -92,10 +92,12 @@ MediaStreamPlayback.prototype = {
    * Verifies that media is playing.
    */
   verifyPlaying : function() {
+    var lastStreamTime = this.mediaStream.currentTime;
     var lastElementTime = this.mediaElement.currentTime;
 
     var mediaTimeProgressed = listenUntil(this.mediaElement, 'timeupdate',
-        () => this.mediaElement.currentTime > lastElementTime);
+        () => this.mediaStream.currentTime > lastStreamTime &&
+              this.mediaElement.currentTime > lastElementTime);
 
     return timeout(Promise.all([this.canPlayThroughFired, mediaTimeProgressed]),
                    VERIFYPLAYING_TIMEOUT_LENGTH, "verifyPlaying timed out")

dom/media/tests/mochitest/test_peerConnection_callbacks.html

@@ -75,7 +75,7 @@ runNetworkTest(function() {
     .then(() => pcall(pc1, pc1.setRemoteDescription, pc2.localDescription))
     .then(() => delivered)
   //    .then(() => canPlayThrough)    // why doesn't this fire?
-    .then(() => waitUntil(() => v2.currentTime > 0))
+    .then(() => waitUntil(() => v2.currentTime > 0 && v2.srcObject.currentTime > 0))
     .then(() => ok(v2.currentTime > 0, "v2.currentTime is moving (" + v2.currentTime + ")"))
     .then(() => ok(true, "Connected."))
     .then(() => pcall(pc1, pc1.getStats, null))

dom/media/tests/mochitest/test_peerConnection_promiseSendOnly.html

@@ -51,7 +51,7 @@
     .then(() => pc1.setRemoteDescription(pc2.localDescription))
     .then(() => delivered)
 //    .then(() => canPlayThrough)    // why doesn't this fire?
-    .then(() => waitUntil(() => v2.currentTime > 0))
+    .then(() => waitUntil(() => v2.currentTime > 0 && v2.srcObject.currentTime > 0))
     .then(() => ok(v2.currentTime > 0, "v2.currentTime is moving (" + v2.currentTime + ")"))
     .then(() => ok(true, "Connected."))
     .catch(reason => ok(false, "unexpected failure: " + reason))

dom/media/tests/mochitest/test_peerConnection_scaleResolution.html

@@ -64,7 +64,7 @@
 
     await v2loadedmetadata;
 
-    await waitUntil(() => v2.currentTime > 0);
+    await waitUntil(() => v2.currentTime > 0 && v2.srcObject.currentTime > 0);
     ok(v2.currentTime > 0, "v2.currentTime is moving (" + v2.currentTime + ")");
 
     ok(v1.videoWidth > 0, "source width is positive");

dom/webidl/MediaStream.webidl

@@ -39,6 +39,7 @@ interface MediaStream : EventTarget {
     readonly    attribute boolean      active;
                 attribute EventHandler onaddtrack;
                 attribute EventHandler onremovetrack;
+    readonly attribute double currentTime;
 
     [ChromeOnly, Throws]
     static Promise<long> countUnderlyingStreams();