[cast_channel] Make cast_channel related files not depend on "cast_channel.h"

extensions/browser/api/cast_channel/cast_framer.h

Index: extensions/browser/api/cast_channel/cast_framer.h
diff --git a/extensions/browser/api/cast_channel/cast_framer.h b/extensions/browser/api/cast_channel/cast_framer.h
index ec8fcfe6088d95069bcadca0ccdb629f3ff1c105..8a5b6b535ff188d86765f8418c8949f4a32588fe 100644
--- a/extensions/browser/api/cast_channel/cast_framer.h
+++ b/extensions/browser/api/cast_channel/cast_framer.h
@@ -12,7 +12,7 @@
 #include <string>
 
 #include "base/macros.h"
-#include "extensions/common/api/cast_channel.h"
+#include "components/cast_channel/cast_channel_enum.h"
 #include "net/base/io_buffer.h"
 
 namespace extensions {
@@ -23,6 +23,8 @@ class CastMessage;
 // Class for constructing and parsing CastMessage packet data.
 class MessageFramer {
  public:
+  using ChannelError = ::cast_channel::ChannelError;
+
   // |input_buffer|: The input buffer used by all socket read operations that
   //                 feed data into the framer.
   explicit MessageFramer(scoped_refptr<net::GrowableIOBuffer> input_buffer);