[tbb-commits] [tor-browser/tor-browser-45.2.0esr-6.5-1] fixup! Bug 1517: Reduce precision of time for Javascript.

[gk at torproject.org]

commit 49d0c6389eea055e94a8fb492bd95de56b9111a4
Author: Arthur Edelstein <arthuredelstein at gmail.com>
Date:   Fri May 27 12:39:10 2016 -0700

    fixup! Bug 1517: Reduce precision of time for Javascript.
---
 dom/html/HTMLMediaElement.cpp       | 8 +++++++-
 dom/html/HTMLMediaElement.h         | 3 +++
 dom/media/DOMMediaStream.cpp        | 3 ++-
 dom/media/webaudio/AudioContext.cpp | 6 ++++--
 4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/dom/html/HTMLMediaElement.cpp b/dom/html/HTMLMediaElement.cpp
index 393ddb1..6bd644c 100644
--- a/dom/html/HTMLMediaElement.cpp
+++ b/dom/html/HTMLMediaElement.cpp
@@ -1403,7 +1403,7 @@ NS_IMETHODIMP HTMLMediaElement::GetSeeking(bool* aSeeking)
 }
 
 double
-HTMLMediaElement::CurrentTime() const
+HTMLMediaElement::CurrentTimeImpl() const
 {
   if (MediaStream* stream = GetSrcMediaStream()) {
     if (mSrcStreamPausedCurrentTime >= 0) {
@@ -1419,6 +1419,12 @@ HTMLMediaElement::CurrentTime() const
   return mDefaultPlaybackStartPosition;
 }
 
+double
+HTMLMediaElement::CurrentTime() const
+{
+  return floor(10 * CurrentTimeImpl()) / 10;
+}
+
 NS_IMETHODIMP HTMLMediaElement::GetCurrentTime(double* aCurrentTime)
 {
   *aCurrentTime = CurrentTime();
diff --git a/dom/html/HTMLMediaElement.h b/dom/html/HTMLMediaElement.h
index ed95ad6..3909e50 100644
--- a/dom/html/HTMLMediaElement.h
+++ b/dom/html/HTMLMediaElement.h
@@ -1527,6 +1527,9 @@ private:
   // initially be set to zero seconds. This time is used to allow the element to
   // be seeked even before the media is loaded.
   double mDefaultPlaybackStartPosition;
+
+  // The unrounded current time
+  double CurrentTimeImpl() const;
 };
 
 } // namespace dom
diff --git a/dom/media/DOMMediaStream.cpp b/dom/media/DOMMediaStream.cpp
index fc56140..40d09c3 100644
--- a/dom/media/DOMMediaStream.cpp
+++ b/dom/media/DOMMediaStream.cpp
@@ -448,8 +448,9 @@ DOMMediaStream::CurrentTime()
   if (!mPlaybackStream) {
     return 0.0;
   }
-  return mPlaybackStream->
+  double currentTime = mPlaybackStream->
     StreamTimeToSeconds(mPlaybackStream->GetCurrentTime() - mLogicalStreamStartTime);
+  return floor(10 * currentTime) / 10;
 }
 
 void
diff --git a/dom/media/webaudio/AudioContext.cpp b/dom/media/webaudio/AudioContext.cpp
index 2bb4242..c7c399b 100644
--- a/dom/media/webaudio/AudioContext.cpp
+++ b/dom/media/webaudio/AudioContext.cpp
@@ -672,8 +672,10 @@ double
 AudioContext::CurrentTime() const
 {
   MediaStream* stream = Destination()->Stream();
-  return stream->StreamTimeToSeconds(stream->GetCurrentTime() +
-                                     Destination()->ExtraCurrentTime());
+  double currentTime = stream->StreamTimeToSeconds(
+    stream->GetCurrentTime() + Destination()->ExtraCurrentTime());
+  // Round to the latest 100 ms.
+  return floor(10 * currentTime) / 10;
 }
 
 void