lint: Check eslint indentation for casper tests.

Now we just limit this rule for the node tests themselves.

frontend_tests/.eslintrc.json

@@ -14,7 +14,6 @@
     },
     "rules": {
         "no-sync": 0,
-        "indent": 0,
         "prefer-const": "error"
     }
 }

frontend_tests/node_tests/.eslintrc.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "indent": 0
+    }
+}

frontend_tests/zjsunit/bugdown_assert.js

@@ -31,7 +31,8 @@ let _markdownComparerInstance = null;
 class MarkdownComparer {
     constructor(output_formatter) {
         this._output_formatter = output_formatter || function (actual, expected) {
-            return ["Actual and expected output do not match.",
+            return [
+                "Actual and expected output do not match.",
                 actual,
                 "!=",
                 expected,