tools: add multiple locations support in license builder

LICENSE

@@ -1251,7 +1251,7 @@ The externally maintained libraries used by Node.js are:
     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   """
 
-- gtest, located at src/gtest and test/cctest/gtest, is licensed as follows:
+- gtest, located at src/gtest, test/cctest/gtest, is licensed as follows:
   """
     Copyright 2008, Google Inc.
     All rights reserved.

tools/license-builder.sh

@@ -8,14 +8,27 @@ licensehead="$(sed '/^- /,$d' "${licensefile}")"
 tmplicense="${rootdir}/~LICENSE.$$"
 echo "$licensehead" > "$tmplicense"
 
+join_by() {
+  local d=${1-} f=${2-}
+  if shift 2; then
+    printf %s "$f" "${@/#/$d}"
+  fi
+}
+
 
 # addlicense <library> <location> <license text>
 addlicense() {
+  argv=("$@")
+  location_count=$(expr $# - 2)
+  locations=("${argv[@]:1:location_count}")
+  location_str=$(join_by ", " ${locations[@]})
+
+  license=("${argv[@]: -1:1}")
 
   echo "
-- ${1}, located at ${2}, is licensed as follows:
+- ${1}, located at ${location_str}, is licensed as follows:
   \"\"\"
-$(echo "$3" | sed -e 's/^/    /' -e 's/^    $//' -e 's/ *$//' | sed -e '/./,$!d' | sed -e '/^$/N;/^\n$/D')
+$(echo "$license" | sed -e 's/^/    /' -e 's/^    $//' -e 's/ *$//' | sed -e '/./,$!d' | sed -e '/^$/N;/^\n$/D')
   \"\"\"\
 " >> "$tmplicense"
 
@@ -83,7 +96,7 @@ addlicense "cpplint.py" "tools/cpplint.py" \
            "$(sed -e '/^$/,$d' -e 's/^#$//' -e 's/^# //' "${rootdir}"/tools/cpplint.py | tail -n +3)"
 addlicense "ESLint" "tools/node_modules/eslint" "$(cat "${rootdir}"/tools/node_modules/eslint/LICENSE)"
 addlicense "Babel" "tools/node_modules/@babel" "$(cat "${rootdir}"/tools/node_modules/@babel/core/LICENSE)"
-addlicense "gtest" "test/cctest/gtest" "$(cat "${rootdir}"/test/cctest/gtest/LICENSE)"
+addlicense "gtest" "src/gtest" "test/cctest/gtest" "$(cat "${rootdir}"/test/cctest/gtest/LICENSE)"
 
 # nghttp2
 addlicense "nghttp2" "deps/nghttp2" "$(cat "${rootdir}"/deps/nghttp2/COPYING)"