Bug 1786402 - Fix ESLint rule warnings for no-unused-vars in...

Bug 1786402 - Fix ESLint rule warnings for no-unused-vars in intl/uconv/tests/unit/test_bug340714.js r=hsivonen

Differential Revision: https://phabricator.services.mozilla.com/D155290

.eslintrc.js

@@ -176,7 +176,6 @@ module.exports = {
         // per bug.
         "extensions/permissions/**",
         "image/test/unit/**",
-        "intl/uconv/tests/unit/test_bug340714.js",
         "modules/libjar/test/unit/test_empty_jar_telemetry.js",
         "modules/libjar/zipwriter/test/unit/test_alignment.js",
         "modules/libjar/zipwriter/test/unit/test_bug419769_2.js",

intl/uconv/tests/unit/test_bug340714.js

@@ -28,16 +28,10 @@ registerCleanupFunction(() => {
 });
 
 function makeText(withBOM, charset) {
-  // eslint-disable-next-line no-eval
-  var theText = eval("sample" + charset);
-  if (withBOM) {
-    if (charset == "UTF16BE") {
-      theText = beBOM + theText;
-    } else {
-      theText = leBOM + theText;
-    }
-  }
-  return theText;
+  const isBE = charset === "UTF16BE";
+  const sampleText = isBE ? sampleUTF16BE : sampleUTF16LE;
+  const bom = isBE ? beBOM : leBOM;
+  return withBOM ? bom + sampleText : sampleText;
 }
 
 function testCase(withBOM, charset, charsetDec, decoder, bufferLength) {