fix(document): surface errors in subdoc pre validate

Fix #7187

Author: vkarpov15

lib/schema/documentarray.js

@@ -164,8 +164,11 @@ DocumentArray.prototype.doValidate = function(array, fn, scope, options) {
     // them :(
 
     function callback(err) {
-      if (err) {
+      if (err != null) {
         error = err;
+        if (error.name !== 'ValidationError') {
+          error.$isArrayValidatorError = true;
+        }
       }
       --count || fn(error);
     }

test/document.test.js

@@ -6379,11 +6379,11 @@ describe('document', function() {
 
   it('surfaces errors in subdoc pre validate (gh-7187)', function() {
     const InnerSchema = new Schema({ name: String });
-    
+
     InnerSchema.pre('validate', function() {
       throw new Error('Oops!');
     });
-    
+
     const TestSchema = new Schema({ subdocs: [InnerSchema] });
 
     const Test = db.model('gh7187', TestSchema);