WebRtcVideoFrame: Initialize members in empty constructor

R=pbos@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/41319004

Cr-Commit-Position: refs/heads/master@{#8746}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8746 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/media/webrtc/webrtcvideoframe.cc b/talk/media/webrtc/webrtcvideoframe.cc
index 1738777..a1afea6 100644
--- a/talk/media/webrtc/webrtcvideoframe.cc
+++ b/talk/media/webrtc/webrtcvideoframe.cc
@@ -39,7 +39,12 @@
 
 namespace cricket {
 
-WebRtcVideoFrame::WebRtcVideoFrame() {}
+WebRtcVideoFrame::WebRtcVideoFrame():
+    pixel_width_(0),
+    pixel_height_(0),
+    elapsed_time_ns_(0),
+    time_stamp_ns_(0),
+    rotation_(webrtc::kVideoRotation_0) {}
 
 WebRtcVideoFrame::WebRtcVideoFrame(
     const rtc::scoped_refptr<webrtc::VideoFrameBuffer>& buffer,