fix(ngModel): correct minErr ussage for correct doc creation

Remove the `new` from the minErr assignment, so the closure compiler
can detect the errors correctly. Also removes the leading $ from the
variable name to be consistent with the Angular.js file.

Closes #12386

Author: Narretz

src/ng/directive/input.js

@@ -6,7 +6,7 @@
   DIRTY_CLASS: false,
   UNTOUCHED_CLASS: false,
   TOUCHED_CLASS: false,
-  $ngModelMinErr: false,
+  ngModelMinErr: false,
 */
 
 // Regex code is obtained from SO: https://stackoverflow.com/questions/3143070/javascript-regex-iso-datetime#answer-3143231
@@ -1243,7 +1243,7 @@ function createDateInputType(type, regexp, parseDate, format) {
 
     ctrl.$formatters.push(function(value) {
       if (value && !isDate(value)) {
-        throw $ngModelMinErr('datefmt', 'Expected `{0}` to be a date', value);
+        throw ngModelMinErr('datefmt', 'Expected `{0}` to be a date', value);
       }
       if (isValidDate(value)) {
         previousDate = value;
@@ -1319,7 +1319,7 @@ function numberInputType(scope, element, attr, ctrl, $sniffer, $browser) {
   ctrl.$formatters.push(function(value) {
     if (!ctrl.$isEmpty(value)) {
       if (!isNumber(value)) {
-        throw $ngModelMinErr('numfmt', 'Expected `{0}` to be a number', value);
+        throw ngModelMinErr('numfmt', 'Expected `{0}` to be a number', value);
       }
       value = value.toString();
     }
@@ -1412,7 +1412,7 @@ function parseConstantExpr($parse, context, name, expression, fallback) {
   if (isDefined(expression)) {
     parseFn = $parse(expression);
     if (!parseFn.constant) {
-      throw minErr('ngModel')('constexpr', 'Expected constant expression for `{0}`, but saw ' +
+      throw ngModelMinErr('constexpr', 'Expected constant expression for `{0}`, but saw ' +
                                    '`{1}`.', name, expression);
     }
     return parseFn(context);

src/ng/directive/ngModel.js

@@ -16,8 +16,7 @@ var VALID_CLASS = 'ng-valid',
     TOUCHED_CLASS = 'ng-touched',
     PENDING_CLASS = 'ng-pending';
 
-
-var $ngModelMinErr = new minErr('ngModel');
+var ngModelMinErr = minErr('ngModel');
 
 /**
  * @ngdoc type
@@ -268,7 +267,7 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
         }
       };
     } else if (!parsedNgModel.assign) {
-      throw $ngModelMinErr('nonassign', "Expression '{0}' is non-assignable. Element: {1}",
+      throw ngModelMinErr('nonassign', "Expression '{0}' is non-assignable. Element: {1}",
           $attr.ngModel, startingTag($element));
     }
   };
@@ -599,7 +598,7 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
       forEach(ctrl.$asyncValidators, function(validator, name) {
         var promise = validator(modelValue, viewValue);
         if (!isPromiseLike(promise)) {
-          throw $ngModelMinErr("$asyncValidators",
+          throw ngModelMinErr("$asyncValidators",
             "Expected asynchronous validator to return a promise but got '{0}' instead.", promise);
         }
         setValidity(name, undefined);