bug 1214493 restore fractional start time accidentally rounded in 13e85dc6b41b r=padenot

--HG--
extra : rebase_source : 524269e54597bffcdeafc96940cbe14b8850c6a7

dom/media/webaudio/AudioBufferSourceNode.cpp

@@ -97,7 +97,7 @@ public:
     switch (aIndex) {
     case AudioBufferSourceNode::START:
       MOZ_ASSERT(!mStart, "Another START?");
-      mStart = mDestination->SecondsToNearestStreamTime(aParam);
+      mStart = aParam * mDestination->SampleRate();
       // Round to nearest
       mBeginProcessing = mStart + 0.5;
       break;