Fix some uninitialized variables in convert_legacy_video_factory

This is causing compilation failure on Chrome on Windows using MSVC
64bits.

TBR=andersc@webrtc.org

Bug: chromium:787192
Change-Id: If82290a9d7373385de4820b34f2c7dc9225c3d95
Reviewed-on: https://webrtc-review.googlesource.com/24981
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20821}
diff --git a/media/engine/convert_legacy_video_factory.cc b/media/engine/convert_legacy_video_factory.cc
index e562a02..4e92c82 100644
--- a/media/engine/convert_legacy_video_factory.cc
+++ b/media/engine/convert_legacy_video_factory.cc
@@ -72,6 +72,8 @@
   webrtc::VideoEncoderFactory::CodecInfo QueryVideoEncoder(
       const webrtc::SdpVideoFormat& format) const override {
     CodecInfo info;
+    info.has_internal_source = false;
+    info.is_hardware_accelerated = false;
     if (!external_encoder_factory_)
       return info;