Merge pull request #2079 from google/hotfix/hide-number-spinners

Hide number spinners for textfields.

src/textfield/_textfield.scss

@@ -66,6 +66,16 @@
   text-align: left;
   color: inherit;
 
+  &[type="number"] {
+    -moz-appearance: textfield;
+  }
+
+  &[type="number"]::-webkit-inner-spin-button,
+  &[type="number"]::-webkit-outer-spin-button {
+    -webkit-appearance: none;
+    margin: 0;
+  }
+
   .mdl-textfield.is-focused & {
     outline: none;
   }