Extract special BUILD file for //tools/cpp when present in the @bazel_tools

Progress towards #10134.

RELNOTES: None.
PiperOrigin-RevId: 280654359

Author: hlopko

scripts/bootstrap/compile.sh

@@ -289,6 +289,7 @@ EOF
 
   # Create the rest of @bazel_tools//tools/...
   link_children "${PWD}" tools/cpp "${BAZEL_TOOLS_REPO}"
+  mv -f ${BAZEL_TOOLS_REPO}/tools/cpp/BUILD.tools ${BAZEL_TOOLS_REPO}/tools/cpp/BUILD
   link_children "${PWD}" tools/python "${BAZEL_TOOLS_REPO}"
   link_children "${PWD}" tools "${BAZEL_TOOLS_REPO}"
 

src/create_embedded_tools.py

@@ -33,6 +33,7 @@
      lambda x: 'tools/build_defs/repo/BUILD'),
     ('*tools/platforms/BUILD.tools', lambda x: 'platforms/BUILD'),
     ('*tools/platforms/*', lambda x: 'platforms/' + os.path.basename(x)),
+    ('*tools/cpp/BUILD.tools', lambda x: 'tools/cpp/BUILD'),
     ('*tools/cpp/runfiles/generated_*',
      lambda x: 'tools/cpp/runfiles/' + os.path.basename(x)[len('generated_'):]),
     ('*jarjar_command_deploy.jar',