Revert 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 f8a04f2e74a9056bf5dbdc4b676e820e83c1ac8a..3a997176a980b6aafc9fda79dfe8de89c84cb7f3 100644
--- a/webrtc/video_encoder.h
+++ b/webrtc/video_encoder.h
@@ -63,6 +63,19 @@
 
 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();