(core) Update ACL resources/rules when tables/columns get renamed

Summary:
- Placed rule-updating functions in acl.py.
- Reset UI when rules update externally, or alert the user to reset if there
  are pending local changes.
- Removed some unused and distracting bits from client-side DocModel.

A few improvements related to poor error handling:
- In case of missing DocActions (tickled by broken ACL rule handling), don't
  add to confusion by attempting to process bad actions
- In case of missing attributes in ACL formulas, return undefined rather than
  fail; the latter creates more problems.
- In case in invalid rules, fail rather than skip; this feels more correct now
  that we have error checking and recovery option, and helps avoid invalid rules.
- Prevent saving invalid rules with an empty ACL formula.
- Fix bug with rule positions.

Test Plan: Added a python and browser test for table/column renames.

Reviewers: paulfitz

Reviewed By: paulfitz

Differential Revision: https://phab.getgrist.com/D2698

app/server/lib/ACLFormula.ts

@@ -86,12 +86,8 @@ function getAttr(value: any, attrName: string, valueNode: ParsedAclFormula): any
     }
     throw new Error(`No value for '${describeNode(valueNode)}'`);
   }
-  const result = (typeof value.get === 'function' ? value.get(attrName) : // InfoView
-                  value[attrName]);
-  if (result === undefined) {
-    throw new Error(`No attribute '${describeNode(valueNode)}.${attrName}'`);
-  }
-  return result;
+  return (typeof value.get === 'function' ? value.get(attrName) : // InfoView
+          value[attrName]);
 }
 
 /**

app/server/lib/GranularAccess.ts

@@ -1090,14 +1090,14 @@ export class RecordView implements InfoView {
     if (colId === 'id') {
       return this.data[2][this.index];
     }
-    return this.data[3][colId][this.index];
+    return this.data[3][colId]?.[this.index];
   }
 
   public toJSON() {
     if (this.index === undefined) { return {}; }
     const results: {[key: string]: any} = {};
     for (const key of Object.keys(this.data[3])) {
-      results[key] = this.data[3][key][this.index];
+      results[key] = this.data[3][key]?.[this.index];
     }
     return results;
   }