Revert "Remove backwards compatibility functions in openssl"

This reverts commit 4db5b979b749ce1141d1406391499715e697f34d.

Reason for revert: Breaks downstream project

Original change's description:
> Remove backwards compatibility functions in openssl
>
> After changing base functions to a CHECK instead of an =0, these
> are no longer needed.
>
> Bug: webrtc:14632
> Change-Id: If3f1a62905cf433486f4974b2153c9210d1e045b
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/283542
> Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
> Commit-Queue: Harald Alvestrand <hta@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#38643}

Bug: webrtc:14632
Change-Id: I4c0ec753285fab882f60b059b3d34f772bf5f7e7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/283721
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Auto-Submit: Mirko Bonadei <mbonadei@webrtc.org>
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Owners-Override: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38649}
diff --git a/rtc_base/openssl_stream_adapter.cc b/rtc_base/openssl_stream_adapter.cc
index 9fd8c8f..5fa1a3c 100644
--- a/rtc_base/openssl_stream_adapter.cc
+++ b/rtc_base/openssl_stream_adapter.cc
@@ -561,6 +561,21 @@
 //
 // StreamInterface Implementation
 //
+// Backwards compatible Write() method using deprecated API.
+// Needed because deprecated API is still =0 in API definition.
+StreamResult OpenSSLStreamAdapter::Write(const void* data,
+                                         size_t data_len,
+                                         size_t* written,
+                                         int* error) {
+  // TODO(bugs.webrtc.org/14632): Consider doing
+  // RTC_CHECK_NOTREACHED(); when downstream usage is eliminated.
+  size_t dummy_written;
+  int dummy_error;
+  return Write(
+      rtc::MakeArrayView(reinterpret_cast<const uint8_t*>(data), data_len),
+      written ? *written : dummy_written, error ? *error : dummy_error);
+}
+
 StreamResult OpenSSLStreamAdapter::Write(rtc::ArrayView<const uint8_t> data,
                                          size_t& written,
                                          int& error) {
@@ -622,6 +637,19 @@
   // not reached
 }
 
+// Backwards compatible Read() method using deprecated API.
+StreamResult OpenSSLStreamAdapter::Read(void* data,
+                                        size_t data_len,
+                                        size_t* read,
+                                        int* error) {
+  // TODO(bugs.webrtc.org/14632): Consider doing
+  // RTC_CHECK_NOTREACHED() when downstream usage is thought to be eliminated.
+  size_t dummy_read;
+  int dummy_error;
+  return Read(rtc::MakeArrayView(reinterpret_cast<uint8_t*>(data), data_len),
+              read ? *read : dummy_read, error ? *error : dummy_error);
+}
+
 StreamResult OpenSSLStreamAdapter::Read(rtc::ArrayView<uint8_t> data,
                                         size_t& read,
                                         int& error) {
diff --git a/rtc_base/openssl_stream_adapter.h b/rtc_base/openssl_stream_adapter.h
index aee8d36..3c94ecd 100644
--- a/rtc_base/openssl_stream_adapter.h
+++ b/rtc_base/openssl_stream_adapter.h
@@ -95,9 +95,16 @@
   void SetMaxProtocolVersion(SSLProtocolVersion version) override;
   void SetInitialRetransmissionTimeout(int timeout_ms) override;
 
+  [[deprecated("bugs.webrtc.org/14632")]] StreamResult
+  Read(void* data, size_t data_len, size_t* read, int* error) override;
   StreamResult Read(rtc::ArrayView<uint8_t> data,
                     size_t& read,
                     int& error) override;
+  [[deprecated("bugs.webrtc.org/14632")]] StreamResult Write(
+      const void* data,
+      size_t data_len,
+      size_t* written,
+      int* error) override;
   StreamResult Write(rtc::ArrayView<const uint8_t> data,
                      size_t& written,
                      int& error) override;