Other EcmaScript version bump

src/ci/docker/host-x86_64/mingw-check/Dockerfile

@@ -61,8 +61,8 @@ ENV SCRIPT python3 ../x.py check --stage 0 --set build.optimized-compiler-builti
            /scripts/validate-toolstate.sh && \
            /scripts/validate-error-codes.sh && \
            reuse --include-submodules lint && \
-           # Runs checks to ensure that there are no ES5 issues in our JS code.
-           es-check es8 ../src/librustdoc/html/static/js/*.js && \
+           # Runs checks to ensure that there are no issues in our JS code.
+           es-check es2019 ../src/librustdoc/html/static/js/*.js && \
            eslint -c ../src/librustdoc/html/static/.eslintrc.js ../src/librustdoc/html/static/js/*.js && \
            eslint -c ../src/tools/rustdoc-js/.eslintrc.js ../src/tools/rustdoc-js/tester.js && \
            eslint -c ../src/tools/rustdoc-gui/.eslintrc.js ../src/tools/rustdoc-gui/tester.js

src/librustdoc/html/static/.eslintrc.js

@@ -5,7 +5,7 @@ module.exports = {
     },
     "extends": "eslint:recommended",
     "parserOptions": {
-        "ecmaVersion": 9,
+        "ecmaVersion": 2019,
         "sourceType": "module"
     },
     "rules": {

src/tools/rustdoc-gui/.eslintrc.js

@@ -6,7 +6,7 @@ module.exports = {
     },
     "extends": "eslint:recommended",
     "parserOptions": {
-        "ecmaVersion": 2018,
+        "ecmaVersion": 2019,
         "sourceType": "module"
     },
     "rules": {

src/tools/rustdoc-js/.eslintrc.js

@@ -6,7 +6,7 @@ module.exports = {
     },
     "extends": "eslint:recommended",
     "parserOptions": {
-        "ecmaVersion": 8,
+        "ecmaVersion": 2019,
         "sourceType": "module"
     },
     "rules": {