From d90b622fa479f4a8185867d940bb1589a11a3a36 Mon Sep 17 00:00:00 2001
From: Craig Hutchison <kb3eua@users.noreply.github.com>
Date: Fri, 30 Sep 2016 23:10:21 -0400
Subject: [PATCH] fix: allow for null values in HTML select options bound with
 ngValue

This corrects the case of <option [ngValue]="null"> binding a string like "{0: null}" to the model instead of an actual null object.

Closes #10349
---
 .../forms/src/directives/select_control_value_accessor.ts     | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/modules/@angular/forms/src/directives/select_control_value_accessor.ts b/modules/@angular/forms/src/directives/select_control_value_accessor.ts
index 54a5f0213b..353c1346b0 100644
--- a/modules/@angular/forms/src/directives/select_control_value_accessor.ts
+++ b/modules/@angular/forms/src/directives/select_control_value_accessor.ts
@@ -115,8 +115,8 @@ export class SelectControlValueAccessor implements ControlValueAccessor {
 
   /** @internal */
   _getOptionValue(valueString: string): any {
-    const value = this._optionMap.get(_extractId(valueString));
-    return value != null ? value : valueString;
+    let key: string = _extractId(valueString);
+    return this._optionMap.has(key) ? this._optionMap.get(key) : valueString;
   }
 }