Bug 1544286 - xpcom/ manual ESLint no-throw-literal fixes. r=erahm

Differential Revision: https://phabricator.services.mozilla.com/D27451

--HG--
extra : moz-landing-system : lando

.eslintrc.js

@@ -84,14 +84,6 @@ module.exports = {
     "rules": {
       "no-undef": "off",
     }
-  }, {
-    // TODO: Bug 1246594. Empty this list once the rule has landed for all dirs
-    "files": [
-      "xpcom/tests/unit/test_iniParser.js",
-    ],
-    "rules": {
-      "no-throw-literal": "off",
-    }
   }, {
     ...removeOverrides(xpcshellTestConfig),
     "files": xpcshellTestPaths.map(path => `${path}**`),

xpcom/tests/unit/test_iniParser.js

@@ -300,6 +300,6 @@ try { parser.setString("ok", "ok", "good="); } catch (e) { caughtError = e; }
 Assert.ok(!caughtError);
 caughtError = null;
 } catch (e) {
-    throw "FAILED in test #" + testnum + " -- " + e;
+    throw new Error(`FAILED in test #${testnum} -- ${e}`);
 }
 }