address comments

Author: mmalerba

src/lib/input/input-value-accessor.ts

@@ -9,5 +9,11 @@
 import {InjectionToken} from '@angular/core';
 
 
+/**
+ * This token is used to inject the object whose value should be set into `MatInput`. If none is
+ * provided, the native `HTMLInputElement` is used. Directives like `MatDatepickerInput` can provide
+ * themselves for this token, in order to make `MatInput` delegate the getting and setting of the
+ * value to them.
+ */
 export const MAT_INPUT_VALUE_ACCESSOR =
-    new InjectionToken<{value: any}>('MAT_INPIUT_VALUE_ACCESSOR');
+    new InjectionToken<{value: any}>('MAT_INPUT_VALUE_ACCESSOR');