Reland of Stop using hardcoded payload types for video codecs

webrtc/video_encoder.h

Index: webrtc/video_encoder.h
diff --git a/webrtc/video_encoder.h b/webrtc/video_encoder.h
index 3a997176a980b6aafc9fda79dfe8de89c84cb7f3..f8a04f2e74a9056bf5dbdc4b676e820e83c1ac8a 100644
--- a/webrtc/video_encoder.h
+++ b/webrtc/video_encoder.h
@@ -63,19 +63,6 @@ class EncodedImageCallback {
 
 class VideoEncoder {
  public:
-  enum EncoderType {
-    kH264,
-    kVp8,
-    kVp9,
-    kUnsupportedCodec,
-  };
-
-  static VideoEncoder* Create(EncoderType codec_type);
-  // Returns true if this type of encoder can be created using
-  // VideoEncoder::Create.
-  static bool IsSupportedSoftware(EncoderType codec_type);
-  static EncoderType CodecToEncoderType(VideoCodecType codec_type);
-
   static VideoCodecVP8 GetDefaultVp8Settings();
   static VideoCodecVP9 GetDefaultVp9Settings();
   static VideoCodecH264 GetDefaultH264Settings();