src: rename misleading arg in ClientHelloParser

Despite being named onend_arg, the pointer is passed both to the
onend_cb and to the onhello_cb. Rename it to cb_arg, which matches the
name of the class field cb_arg_.

PR-URL: #44500
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>

src/crypto/crypto_clienthello-inl.h

@@ -51,7 +51,7 @@ inline void ClientHelloParser::Reset() {
 
 inline void ClientHelloParser::Start(ClientHelloParser::OnHelloCb onhello_cb,
                                      ClientHelloParser::OnEndCb onend_cb,
-                                     void* onend_arg) {
+                                     void* cb_arg) {
   if (!IsEnded())
     return;
   Reset();
@@ -61,7 +61,7 @@ inline void ClientHelloParser::Start(ClientHelloParser::OnHelloCb onhello_cb,
   state_ = kWaiting;
   onhello_cb_ = onhello_cb;
   onend_cb_ = onend_cb;
-  cb_arg_ = onend_arg;
+  cb_arg_ = cb_arg;
 }
 
 inline void ClientHelloParser::End() {

src/crypto/crypto_clienthello.h

@@ -66,7 +66,7 @@ class ClientHelloParser {
   void Parse(const uint8_t* data, size_t avail);
 
   inline void Reset();
-  inline void Start(OnHelloCb onhello_cb, OnEndCb onend_cb, void* onend_arg);
+  inline void Start(OnHelloCb onhello_cb, OnEndCb onend_cb, void* cb_arg);
   inline void End();
   inline bool IsPaused() const;
   inline bool IsEnded() const;