Add buffer pools to build
diff --git a/tools/doxygen/Doxyfile.c++.internal b/tools/doxygen/Doxyfile.c++.internal
index fbe82c8..124f3c6 100644
--- a/tools/doxygen/Doxyfile.c++.internal
+++ b/tools/doxygen/Doxyfile.c++.internal
@@ -886,6 +886,7 @@
src/core/lib/http/format_request.h \
src/core/lib/http/httpcli.h \
src/core/lib/http/parser.h \
+src/core/lib/iomgr/buffer_pool.h \
src/core/lib/iomgr/closure.h \
src/core/lib/iomgr/combiner.h \
src/core/lib/iomgr/endpoint.h \
@@ -1000,6 +1001,7 @@
src/core/lib/http/format_request.c \
src/core/lib/http/httpcli.c \
src/core/lib/http/parser.c \
+src/core/lib/iomgr/buffer_pool.c \
src/core/lib/iomgr/closure.c \
src/core/lib/iomgr/combiner.c \
src/core/lib/iomgr/endpoint.c \