Split codegen target and made it libs
diff --git a/tools/doxygen/Doxyfile.c++ b/tools/doxygen/Doxyfile.c++
index dd5c8ec..edd4ebf 100644
--- a/tools/doxygen/Doxyfile.c++
+++ b/tools/doxygen/Doxyfile.c++
@@ -803,37 +803,7 @@
include/grpc++/support/string_ref.h \
include/grpc++/support/stub_options.h \
include/grpc++/support/sync_stream.h \
-include/grpc++/support/time.h \
-include/grpc++/impl/codegen/async_stream.h \
-include/grpc++/impl/codegen/async_unary_call.h \
-include/grpc++/impl/codegen/call.h \
-include/grpc++/impl/codegen/call_hook.h \
-include/grpc++/impl/codegen/channel_interface.h \
-include/grpc++/impl/codegen/client_context.h \
-include/grpc++/impl/codegen/client_unary_call.h \
-include/grpc++/impl/codegen/completion_queue.h \
-include/grpc++/impl/codegen/completion_queue_tag.h \
-include/grpc++/impl/codegen/config.h \
-include/grpc++/impl/codegen/config_protobuf.h \
-include/grpc++/impl/codegen/grpc_library.h \
-include/grpc++/impl/codegen/method_handler_impl.h \
-include/grpc++/impl/codegen/proto_utils.h \
-include/grpc++/impl/codegen/rpc_method.h \
-include/grpc++/impl/codegen/rpc_service_method.h \
-include/grpc++/impl/codegen/security/auth_context.h \
-include/grpc++/impl/codegen/serialization_traits.h \
-include/grpc++/impl/codegen/server_context.h \
-include/grpc++/impl/codegen/server_interface.h \
-include/grpc++/impl/codegen/service_type.h \
-include/grpc++/impl/codegen/status.h \
-include/grpc++/impl/codegen/status_code_enum.h \
-include/grpc++/impl/codegen/string_ref.h \
-include/grpc++/impl/codegen/stub_options.h \
-include/grpc++/impl/codegen/sync.h \
-include/grpc++/impl/codegen/sync_cxx11.h \
-include/grpc++/impl/codegen/sync_no_cxx11.h \
-include/grpc++/impl/codegen/sync_stream.h \
-include/grpc++/impl/codegen/time.h
+include/grpc++/support/time.h
# This tag can be used to specify the character encoding of the source files
# that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses
diff --git a/tools/doxygen/Doxyfile.c++.internal b/tools/doxygen/Doxyfile.c++.internal
index 13dba2e..50ed2f6 100644
--- a/tools/doxygen/Doxyfile.c++.internal
+++ b/tools/doxygen/Doxyfile.c++.internal
@@ -804,36 +804,6 @@
include/grpc++/support/stub_options.h \
include/grpc++/support/sync_stream.h \
include/grpc++/support/time.h \
-include/grpc++/impl/codegen/async_stream.h \
-include/grpc++/impl/codegen/async_unary_call.h \
-include/grpc++/impl/codegen/call.h \
-include/grpc++/impl/codegen/call_hook.h \
-include/grpc++/impl/codegen/channel_interface.h \
-include/grpc++/impl/codegen/client_context.h \
-include/grpc++/impl/codegen/client_unary_call.h \
-include/grpc++/impl/codegen/completion_queue.h \
-include/grpc++/impl/codegen/completion_queue_tag.h \
-include/grpc++/impl/codegen/config.h \
-include/grpc++/impl/codegen/config_protobuf.h \
-include/grpc++/impl/codegen/grpc_library.h \
-include/grpc++/impl/codegen/method_handler_impl.h \
-include/grpc++/impl/codegen/proto_utils.h \
-include/grpc++/impl/codegen/rpc_method.h \
-include/grpc++/impl/codegen/rpc_service_method.h \
-include/grpc++/impl/codegen/security/auth_context.h \
-include/grpc++/impl/codegen/serialization_traits.h \
-include/grpc++/impl/codegen/server_context.h \
-include/grpc++/impl/codegen/server_interface.h \
-include/grpc++/impl/codegen/service_type.h \
-include/grpc++/impl/codegen/status.h \
-include/grpc++/impl/codegen/status_code_enum.h \
-include/grpc++/impl/codegen/string_ref.h \
-include/grpc++/impl/codegen/stub_options.h \
-include/grpc++/impl/codegen/sync.h \
-include/grpc++/impl/codegen/sync_cxx11.h \
-include/grpc++/impl/codegen/sync_no_cxx11.h \
-include/grpc++/impl/codegen/sync_stream.h \
-include/grpc++/impl/codegen/time.h \
src/cpp/client/secure_credentials.h \
src/cpp/common/secure_auth_context.h \
src/cpp/server/secure_server_credentials.h \
@@ -841,20 +811,6 @@
src/cpp/common/create_auth_context.h \
src/cpp/server/dynamic_thread_pool.h \
src/cpp/server/thread_pool_interface.h \
-include/grpc/impl/codegen/alloc.h \
-include/grpc/impl/codegen/atm.h \
-include/grpc/impl/codegen/atm_gcc_atomic.h \
-include/grpc/impl/codegen/atm_gcc_sync.h \
-include/grpc/impl/codegen/atm_win32.h \
-include/grpc/impl/codegen/log.h \
-include/grpc/impl/codegen/port_platform.h \
-include/grpc/impl/codegen/slice.h \
-include/grpc/impl/codegen/slice_buffer.h \
-include/grpc/impl/codegen/sync.h \
-include/grpc/impl/codegen/sync_generic.h \
-include/grpc/impl/codegen/sync_posix.h \
-include/grpc/impl/codegen/sync_win32.h \
-include/grpc/impl/codegen/time.h \
src/cpp/client/secure_credentials.cc \
src/cpp/common/auth_property_iterator.cc \
src/cpp/common/secure_auth_context.cc \
@@ -886,8 +842,7 @@
src/cpp/util/slice.cc \
src/cpp/util/status.cc \
src/cpp/util/string_ref.cc \
-src/cpp/util/time.cc \
-src/cpp/codegen/grpc_library.cc
+src/cpp/util/time.cc
# This tag can be used to specify the character encoding of the source files
# that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses
diff --git a/tools/doxygen/Doxyfile.core b/tools/doxygen/Doxyfile.core
index a9b14c8..322a33f 100644
--- a/tools/doxygen/Doxyfile.core
+++ b/tools/doxygen/Doxyfile.core
@@ -761,12 +761,6 @@
# Note: If this tag is empty the current directory is searched.
INPUT = include/grpc/grpc_security.h \
-include/grpc/impl/codegen/byte_buffer.h \
-include/grpc/impl/codegen/compression_types.h \
-include/grpc/impl/codegen/connectivity_state.h \
-include/grpc/impl/codegen/grpc_types.h \
-include/grpc/impl/codegen/propagation_bits.h \
-include/grpc/impl/codegen/status.h \
include/grpc/byte_buffer.h \
include/grpc/byte_buffer_reader.h \
include/grpc/compression.h \
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index 502fe39..bed391c 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -761,12 +761,6 @@
# Note: If this tag is empty the current directory is searched.
INPUT = include/grpc/grpc_security.h \
-include/grpc/impl/codegen/byte_buffer.h \
-include/grpc/impl/codegen/compression_types.h \
-include/grpc/impl/codegen/connectivity_state.h \
-include/grpc/impl/codegen/grpc_types.h \
-include/grpc/impl/codegen/propagation_bits.h \
-include/grpc/impl/codegen/status.h \
include/grpc/byte_buffer.h \
include/grpc/byte_buffer_reader.h \
include/grpc/compression.h \