Bump WDP revision to address memory leak

DEPS

@@ -14,7 +14,7 @@ deps = {
   "vendor/bat-native-tweetnacl": "https://github.com/brave-intl/bat-native-tweetnacl.git@800f9d40b7409239ff192e0be634764e747c7a75",
   "vendor/challenge_bypass_ristretto_ffi": "https://github.com/brave-intl/challenge-bypass-ristretto-ffi.git@c5d6d74fdbee467732bcb6b9084514839e656286",
   "vendor/gn-project-generators": "https://github.com/brave/gn-project-generators.git@b76e14b162aa0ce40f11920ec94bfc12da29e5d0",
-  "vendor/web-discovery-project": "https://github.com/brave/web-discovery-project@332821fc8800436d20608420bb87b90d231d9753",
+  "vendor/web-discovery-project": "https://github.com/brave/web-discovery-project@943ba3c98734328f62b5e670bc2e1fd97eef031d",
   "third_party/ethash/src": "https://github.com/chfast/ethash.git@e4a15c3d76dc09392c7efd3e30d84ee3b871e9ce",
   "third_party/bitcoin-core/src": "https://github.com/bitcoin/bitcoin.git@95ea54ba089610019a74c1176a2c7c0dba144b1c",
   "third_party/argon2/src": "https://github.com/P-H-C/phc-winner-argon2.git@62358ba2123abd17fccf2a108a301d4b52c01a7c",

components/webpack/webpack.config.js

@@ -119,7 +119,44 @@ module.exports = async function (env, argv) {
         {
           test: /\.(ttf|eot|ico|svg|png|jpg|jpeg|gif)(\?v=[0-9]\.[0-9]\.[0-9])?$/,
           loader: 'file-loader'
-        }]
+        },
+        // In order to fix a memory leak in WDP we introduced the 'linkedom'
+        // depencendy: https://github.com/brave/web-discovery-project/pull/197
+        //
+        // One of the transitive dependencies of 'linkedom' relies on a
+        // specific export syntax that is not supported by Webpack v4:
+        //
+        // > ERROR in ./vendor/web-discovery-project/node_modules/htmlparser2/lib/esm/index.js 59:9
+        // > Module parse failed: Unexpected token (59:9)
+        // > You may need an appropriate loader to handle this file type,
+        // > currently no loaders are configured to process this file. See
+        // > https://webpack.js.org/concepts#loaders
+        // | return getFeed(parseDOM(feed, options));
+        // | }
+        // > export * as DomUtils from "domutils";
+        //
+        // Updating to Webpack 5 was not possible at this point given the
+        // config to be updated and multiple dependencies and commands that
+        // would break, so instead we added 'babel-loader' specifically for
+        // this problematic file, which allows to support the export syntax.
+        {
+          test: (input) => {
+            // Handle both Windows and Linux/Mac paths formats
+            return (
+              input.endsWith('/htmlparser2/lib/esm/index.js') ||
+              input.endsWith('\\htmlparser2\\lib\\esm\\index.js')
+            );
+          },
+          use: [
+            {
+              loader: 'babel-loader', // This should be the last loader of course
+              options: {
+                plugins: ['@babel/plugin-proposal-export-namespace-from'],
+              },
+            },
+          ],
+        },
+      ]
     },
     node: {
       fs: 'empty'

package.json

@@ -266,6 +266,7 @@
   },
   "devDependencies": {
     "@babel/core": "7.16.0",
+    "@babel/plugin-proposal-export-namespace-from": "7.16.0",
     "@storybook/addon-essentials": "6.4.13",
     "@storybook/addon-knobs": "6.4.0",
     "@storybook/addons": "6.4.13",