Remove memsets of webrtc::CodecSpecificInfo.

CodecSpecificInfo has a default constructor, so initializing by memset is not necessary and is in the way of adding non-trivial members.

Related webrtc CL: https://webrtc-review.googlesource.com/c/src/+/125093

Bug: webrtc:10342
Change-Id: I72a98dbb87c99219fdc389c31f65fbd3a580bd5e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1495533
Commit-Queue: Philip Eliasson <philipel@chromium.org>
Reviewed-by: Lambros Lambrou <lambroslambrou@chromium.org>
Reviewed-by: Henrik Boström <hbos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#637661}

content/renderer/media/webrtc/rtc_video_encoder.cc

@@ -797,7 +797,6 @@ void RTCVideoEncoder::Impl::ReturnEncodedImage(
   }
 
   webrtc::CodecSpecificInfo info;
-  memset(&info, 0, sizeof(info));
   info.codecType = video_codec_type_;
   if (video_codec_type_ == webrtc::kVideoCodecVP8) {
     info.codecSpecific.VP8.keyIdx = -1;

remoting/protocol/webrtc_dummy_video_encoder.cc

@@ -162,7 +162,6 @@ webrtc::EncodedImageCallback::Result WebrtcDummyVideoEncoder::SendEncodedFrame(
   encoded_image.content_type_ = webrtc::VideoContentType::SCREENSHARE;
 
   webrtc::CodecSpecificInfo codec_specific_info;
-  memset(&codec_specific_info, 0, sizeof(codec_specific_info));
   codec_specific_info.codecType = frame.codec;
 
   if (frame.codec == webrtc::kVideoCodecVP8) {