Restore switch kDisableWebRtcHWEncoding

chrome/browser/about_flags.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/about_flags.h"
 
 #include <iterator>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 685 matching lines @@
      IDS_FLAGS_COMPOSITED_LAYER_BORDERS_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(cc::switches::kShowCompositedLayerBorders)},
     {"gl-composited-texture-quad-borders",
      IDS_FLAGS_GL_COMPOSITED_TEXTURE_QUAD_BORDERS,
      IDS_FLAGS_GL_COMPOSITED_TEXTURE_QUAD_BORDERS_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(cc::switches::kGlCompositedTextureQuadBorder)},
 #if BUILDFLAG(ENABLE_WEBRTC)
     {"disable-webrtc-hw-decoding", IDS_FLAGS_WEBRTC_HW_DECODING_NAME,
      IDS_FLAGS_WEBRTC_HW_DECODING_DESCRIPTION, kOsAndroid | kOsCrOS,
      SINGLE_DISABLE_VALUE_TYPE(switches::kDisableWebRtcHWDecoding)},
-    {"disable-webrtc-hw-vp8-encoding", IDS_FLAGS_WEBRTC_HW_VP8_ENCODING_NAME,
-     IDS_FLAGS_WEBRTC_HW_VP8_ENCODING_DESCRIPTION, kOsAndroid | kOsCrOS,
-     SINGLE_DISABLE_VALUE_TYPE(switches::kDisableWebRtcHWVP8Encoding)},
+    {"disable-webrtc-hw-encoding", IDS_FLAGS_WEBRTC_HW_ENCODING_NAME,
+     IDS_FLAGS_WEBRTC_HW_ENCODING_DESCRIPTION, kOsAndroid | kOsCrOS,
+     SINGLE_DISABLE_VALUE_TYPE(switches::kDisableWebRtcHWEncoding)},
     {"enable-webrtc-hw-h264-encoding", IDS_FLAGS_WEBRTC_HW_H264_ENCODING_NAME,
-     IDS_FLAGS_WEBRTC_HW_H264_ENCODING_DESCRIPTION, kOsAndroid | kOsCrOS,
+     IDS_FLAGS_WEBRTC_HW_H264_ENCODING_DESCRIPTION, kOsAndroid,

[Pawel Osciak, 2016/12/15 05:45:53]

This flag is marked here, as well as described in content_features.cc, as only
for Android (although it is actually enabled and being used outside #if
defined(OS_ANDROID) in this CL as far as I can see).

We need to use it outside of Android to keep H264 enabled for CrOS as well.

On the other hand, I think your original intention was to disable only VP8, so
perhaps this flag is not needed at all and you should just be passing
kDisableWebRtcHWVP8Encoding for your use case?

[braveyao, 2016/12/15 20:46:24]

#enable-webrtc-hw-h264-encoding is ENABLED by default on CrOS and Android(and
other platforms). So it won't affect CrOS H264. Here we only add it in
about_flag page on Android to offer a way to disable it manually.

We need this feature flag. Because we need to control the percentage of
deployment if anything goes very wrong.

[Pawel Osciak, 2016/12/20 01:49:17]

Yes, I agree with that. What I meant was that this change changes "kOsAndroid |
kOsCrOS" to "kOsAndroid" only, even though it's not Android-only.

As for the deployment switch, if you needed to disable H264 encode, would you
still want to use VP8 HW encode? If not, you could use kDisableWebRtcHWEncoding
as a disable flag instead of this...

[braveyao, 2016/12/20 19:09:14]

Yes I changed it back to kOsAndroid only since kDisableWebRtcHWEncoding is
restored here.
Now on CrOS, nothing is changed.
On Android, VP8 and H264 can be enable/disable respectively (which is by
design), also can be both disabled by kDisableWebRtcHWEncoding as before.

[Pawel Osciak, 2016/12/21 01:12:57]

I believe before your previous change we could pass a codec name to
kDisableWebRtcHWEncoding to selectively disable codecs... I'm ok using explicit
flags for this instead of a value, but it would be great if that worked not only
on Android...

[braveyao, 2016/12/21 02:01:39]

Done.

I can make the H264 flag also available on CrOS. But I wondering how you can
"disable
codecs selectively using kDisableWebRtcHWEncoding=codecname" on CrOS before. I
didn't see such logic in the codes. 

      FEATURE_VALUE_TYPE(features::kWebRtcHWH264Encoding)},
     {"enable-webrtc-stun-origin", IDS_FLAGS_WEBRTC_STUN_ORIGIN_NAME,
      IDS_FLAGS_WEBRTC_STUN_ORIGIN_DESCRIPTION, kOsAll,
      SINGLE_VALUE_TYPE(switches::kEnableWebRtcStunOrigin)},
 #endif  // ENABLE_WEBRTC
 #if defined(OS_ANDROID)
     {"enable-osk-overscroll", IDS_FLAGS_ENABLE_OSK_OVERSCROLL_NAME,
      IDS_FLAGS_ENABLE_OSK_OVERSCROLL_DESCRIPTION, kOsAndroid,
      SINGLE_VALUE_TYPE(switches::kEnableOSKOverscroll)},
     {"enable-usermedia-screen-capturing", IDS_FLAGS_MEDIA_SCREEN_CAPTURE_NAME,
@@ skipping 1609 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags