Fixes #11266: Apply a pixel-based line-height to date inputs for iOS 7

less/forms.less

@@ -155,6 +155,14 @@ output {
   }
 }
 
+// Special styles for iOS date input
+//
+// In Mobile Safari, date inputs require a pixel line-height that matches the
+// given height of the input.
+input[type="date"] {
+  line-height: @input-height-base;
+}
+
 
 // Form groups
 //