Fix type of local encoded length variable from uint32_t to size_t.

webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc

Index: webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
diff --git a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
index 5e972ff9ac461fb1750c8e1ac7001a2f4e825c98..dcc9cd894ffc69b2594dbb9fd2a07d087667bab9 100644
--- a/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
+++ b/webrtc/modules/video_coding/codecs/vp8/vp8_impl.cc
@@ -978,7 +978,7 @@ int VP8EncoderImpl::GetEncodedPartitions(const VideoFrame& input_image,
            NULL) {
       switch (pkt->kind) {
         case VPX_CODEC_CX_FRAME_PKT: {
-          uint32_t length = encoded_images_[encoder_idx]._length;
+          size_t length = encoded_images_[encoder_idx]._length;
           if (pkt->data.frame.sz + length >
               encoded_images_[encoder_idx]._size) {
             uint8_t* buffer = new uint8_t[pkt->data.frame.sz + length];