[gnome-shell] lint: Add "legacy" configuration

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit e0457b6dc4db716b303a1855d23b65da70f35784
Author: Florian Müllner <fmuellner gnome org>
Date:   Mon Jan 28 01:45:10 2019 +0100

    lint: Add "legacy" configuration
    
    Regarding coding style, gjs is moving in a direction that departs quite
    significantly from the established style, in particular when indenting
    multi-line array/object literals or method arguments:
    
    Currently we are keeping those elements aligned, while the gjs rules now
    expect them to use the regular 4-space indentation.
    
    There are certainly good arguments that can be made for that move - it's
    much less prone to leading to overly-long lines, and matches popluar JS
    styles elsewhere. But switching coding style implies large diffs which
    interfere with git-blame and friends, so in order to allow for a more
    gradual change, add a separate set of "legacy" rules that match more
    closely the style we would expect up to now.
    
    It also disables the rules for quotes and template strings - the former
    because we cannot match the current style to use double-quotes for
    translatable strings and single-quotes otherwise, the latter because
    template strings are still relatively new, so we haven't adopted them
    yet.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/609

 lint/eslintrc-legacy.json | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
---
diff --git a/lint/eslintrc-legacy.json b/lint/eslintrc-legacy.json
new file mode 100644
index 000000000..462607e4e
--- /dev/null
+++ b/lint/eslintrc-legacy.json
@@ -0,0 +1,21 @@
+{
+    "rules": {
+        "indent": [
+            "error",
+            4,
+            {
+                "ignoredNodes": [
+                    "ConditionalExpression",
+                    "CallExpression > ArrowFunctionExpression",
+                    "CallExpression[callee.object.name=GObject][callee.property.name=registerClass] > 
ClassExpression:first-child"
+                ],
+                "CallExpression": { "arguments": "first" },
+                "ArrayExpression": "first",
+                "ObjectExpression": "first",
+                "MemberExpression": "off"
+            }
+        ],
+        "prefer-template": "off",
+        "quotes": "off"
+   }
+}