Fix breaking changes introduced by Eslint v7

Change-Id: I84c3f4c333e9bbe0087738746e879494b90445f1

tools/js/BUILD

@@ -1 +1 @@
-exports_files(["run_npm_binary.py"])
+exports_files(["run_npm_binary.py", "eslint-chdir.js"])

tools/js/eslint-chdir.js

@@ -0,0 +1,30 @@
+/**
+ * @license
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Eslint 7 introduced a breaking change - it uses the current workdir instead
+// of the configuration file directory for resolving relative paths:
+// https://eslint.org/docs/user-guide/migrating-to-7.0.0#base-path-change
+// This file is loaded before the eslint and sets the current directory
+// back to the location of configuration file.
+
+const path = require('path');
+const configParamIndex =
+    process.argv.findIndex(arg => arg === '-c' || arg === '---config');
+if (configParamIndex >= 0 && configParamIndex + 1 < process.argv.length) {
+  const dirName = path.dirname(process.argv[configParamIndex + 1]);
+  process.chdir(dirName);
+}

tools/js/eslint.bzl

@@ -57,9 +57,11 @@ def eslint(name, plugins, srcs, config, ignore, extensions = [".js"], data = [])
         config,
         ignore,
         "//tools/js/eslint-rules:eslint-rules-srcs",
+        "//tools/js:eslint-chdir.js",
         eslint_rules_toplevel_file,
     ] + plugins + data
     common_templated_args = [
+        "--node_options=--require=$$(rlocation $(rootpath //tools/js:eslint-chdir.js))",
         "--ext",
         ",".join(extensions),
         "-c",
@@ -85,7 +87,7 @@ def eslint(name, plugins, srcs, config, ignore, extensions = [".js"], data = [])
             "*_test_require_patch.js",
             "--ignore-pattern",
             "*_test_loader.js",
-            native.package_name(),
+            "./", # Relative to the config file location
         ],
         # Should not run sandboxed.
         tags = [