[Net] Remove StreamPeerTLS.blocking_handshake option.

Which was unused internally, and can be replaced by:

```
while tls.get_status() == tls.STATUS_HANDSHAKING:
  tls.poll()
```

core/io/http_client_tcp.cpp

@@ -364,7 +364,6 @@ Error HTTPClientTCP::poll() {
 						if (!handshaking) {
 							// Connect the StreamPeerTLS and start handshaking.
 							tls_conn = Ref<StreamPeerTLS>(StreamPeerTLS::create());
-							tls_conn->set_blocking_handshake_enabled(false);
 							Error err = tls_conn->connect_to_stream(tcp_connection, conn_host, tls_options);
 							if (err != OK) {
 								close();

core/io/stream_peer_tls.cpp

@@ -41,18 +41,8 @@ StreamPeerTLS *StreamPeerTLS::create() {
 	return nullptr;
 }
 
-bool StreamPeerTLS::available = false;
-
 bool StreamPeerTLS::is_available() {
-	return available;
-}
-
-void StreamPeerTLS::set_blocking_handshake_enabled(bool p_enabled) {
-	blocking_handshake = p_enabled;
-}
-
-bool StreamPeerTLS::is_blocking_handshake_enabled() const {
-	return blocking_handshake;
+	return _create != nullptr;
 }
 
 void StreamPeerTLS::_bind_methods() {
@@ -62,10 +52,6 @@ void StreamPeerTLS::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_status"), &StreamPeerTLS::get_status);
 	ClassDB::bind_method(D_METHOD("get_stream"), &StreamPeerTLS::get_stream);
 	ClassDB::bind_method(D_METHOD("disconnect_from_stream"), &StreamPeerTLS::disconnect_from_stream);
-	ClassDB::bind_method(D_METHOD("set_blocking_handshake_enabled", "enabled"), &StreamPeerTLS::set_blocking_handshake_enabled);
-	ClassDB::bind_method(D_METHOD("is_blocking_handshake_enabled"), &StreamPeerTLS::is_blocking_handshake_enabled);
-
-	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "blocking_handshake"), "set_blocking_handshake_enabled", "is_blocking_handshake_enabled");
 
 	BIND_ENUM_CONSTANT(STATUS_DISCONNECTED);
 	BIND_ENUM_CONSTANT(STATUS_HANDSHAKING);

core/io/stream_peer_tls.h

@@ -41,10 +41,6 @@ protected:
 	static StreamPeerTLS *(*_create)();
 	static void _bind_methods();
 
-	static bool available;
-
-	bool blocking_handshake = true;
-
 public:
 	enum Status {
 		STATUS_DISCONNECTED,
@@ -54,9 +50,6 @@ public:
 		STATUS_ERROR_HOSTNAME_MISMATCH
 	};
 
-	void set_blocking_handshake_enabled(bool p_enabled);
-	bool is_blocking_handshake_enabled() const;
-
 	virtual void poll() = 0;
 	virtual Error accept_stream(Ref<StreamPeer> p_base, Ref<TLSOptions> p_options) = 0;
 	virtual Error connect_to_stream(Ref<StreamPeer> p_base, const String &p_common_name, Ref<TLSOptions> p_options) = 0;

doc/classes/StreamPeerTLS.xml

@@ -53,10 +53,6 @@
 			</description>
 		</method>
 	</methods>
-	<members>
-		<member name="blocking_handshake" type="bool" setter="set_blocking_handshake_enabled" getter="is_blocking_handshake_enabled" default="true">
-		</member>
-	</members>
 	<constants>
 		<constant name="STATUS_DISCONNECTED" value="0" enum="Status">
 			A status representing a [StreamPeerTLS] that is disconnected.

modules/mbedtls/stream_peer_mbedtls.cpp

@@ -80,9 +80,11 @@ void StreamPeerMbedTLS::_cleanup() {
 }
 
 Error StreamPeerMbedTLS::_do_handshake() {
-	int ret = 0;
-	while ((ret = mbedtls_ssl_handshake(tls_ctx->get_context())) != 0) {
-		if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
+	int ret = mbedtls_ssl_handshake(tls_ctx->get_context());
+	if (ret == MBEDTLS_ERR_SSL_WANT_READ || ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
+		// Handshake is still in progress, will retry via poll later.
+		return OK;
+	} else if (ret != 0) {
 		// An error occurred.
 		ERR_PRINT("TLS handshake error: " + itos(ret));
 		TLSContextMbedTLS::print_mbedtls_error(ret);
@@ -91,13 +93,6 @@ Error StreamPeerMbedTLS::_do_handshake() {
 		return FAILED;
 	}
 
-		// Handshake is still in progress.
-		if (!blocking_handshake) {
-			// Will retry via poll later
-			return OK;
-		}
-	}
-
 	status = STATUS_CONNECTED;
 	return OK;
 }
@@ -306,10 +301,8 @@ StreamPeerTLS *StreamPeerMbedTLS::_create_func() {
 
 void StreamPeerMbedTLS::initialize_tls() {
 	_create = _create_func;
-	available = true;
 }
 
 void StreamPeerMbedTLS::finalize_tls() {
-	available = false;
 	_create = nullptr;
 }

modules/websocket/wsl_peer.cpp

@@ -333,7 +333,6 @@ void WSLPeer::_do_client_handshake() {
 			// Start SSL handshake
 			tls = Ref<StreamPeerTLS>(StreamPeerTLS::create());
 			ERR_FAIL_COND_MSG(tls.is_null(), "SSL is not available in this build.");
-			tls->set_blocking_handshake_enabled(false);
 			if (tls->connect_to_stream(tcp, requested_host, tls_options) != OK) {
 				close(-1);
 				return; // Error.

platform/web/export/editor_http_server.h

@@ -205,7 +205,6 @@ public:
 			if (tls.is_null()) {
 				tls = Ref<StreamPeerTLS>(StreamPeerTLS::create());
 				peer = tls;
-				tls->set_blocking_handshake_enabled(false);
 				if (tls->accept_stream(tcp, TLSOptions::server(key, cert)) != OK) {
 					_clear_client();
 					return;