Add some details

Author: vjpai

doc/core/moving-to-c++.md

@@ -6,14 +6,17 @@ ctiller, markdroth, vjpai
 
 ## Background and Goal
 
-gRPC core was originally written in C89 for several reasons (possibility of
-kernel integration, ease of wrapping, compiler support, etc). Over time, this
-was changed to C99 as all relevant compilers in active use came to support C99
-effectively. Now, gRPC core is C++ (although the code is still idiomatically C
-code) with C linkage for public functions. Throughout all of these transitions,
-the public header files are committed to remain in C89.
-
-The goal now is to make gRPC core true idiomatic C++ compatible with
+gRPC core was originally written in C89 for several reasons
+(possibility of kernel integration, ease of wrapping, compiler
+support, etc). Over time, this was changed to C99 as all relevant
+compilers in active use came to support C99 effectively.
+[Now, gRPC core is C++](https://github.com/grpc/proposal/blob/master/L6-allow-c%2B%2B-in-grpc-core.md)
+(although the code is still idiomatically C code) with C linkage for
+public functions. Throughout all of these transitions, the public
+header files are committed to remain in C89.
+
+The goal now is to make the gRPC core implementation true idiomatic
+C++ compatible with
 [Google's C++ style guide](https://google.github.io/styleguide/cppguide.html).
 
 ## Constraints
@@ -48,7 +51,10 @@ The goal now is to make gRPC core true idiomatic C++ compatible with
 
 ## Implications for C++ API and wrapped languages
 
-- For C++ structs, switch to `using` when possible (e.g., Slice, ByteBuffer, ...)
+- For C++ structs, switch to `using` when possible (e.g., Slice,
+ByteBuffer, ...)
+- The C++ API implementation might directly start using
+`grpc_transport_stream_op_batch` rather than the core surface `grpc_op`.
 - Can we get wrapped languages to a point where we can statically link C++? This will take a year in probability but that would allow the use of `std::`
   - Are there other environments that don't support std library, like maybe Android NDK?
     - Probably, that might push things out to 18 months

tools/doxygen/Doxyfile.core

@@ -772,6 +772,7 @@ doc/connection-backoff-interop-test-description.md \
 doc/connection-backoff.md \
 doc/connectivity-semantics-and-api.md \
 doc/core/grpc-error.md \
+doc/core/moving-to-c++.md \
 doc/core/pending_api_cleanups.md \
 doc/cpp-style-guide.md \
 doc/environment_variables.md \

tools/doxygen/Doxyfile.core.internal

@@ -772,6 +772,7 @@ doc/connection-backoff-interop-test-description.md \
 doc/connection-backoff.md \
 doc/connectivity-semantics-and-api.md \
 doc/core/grpc-error.md \
+doc/core/moving-to-c++.md \
 doc/core/pending_api_cleanups.md \
 doc/cpp-style-guide.md \
 doc/environment_variables.md \