fix(text-field): Changes to text area label positioning to cover text…

… content.

Other changes:
  - RTL position fix for text area label.
  - User can now scroll the text area content when hovering on label.

packages/mdc-textfield/_mixins.scss

@@ -494,15 +494,16 @@
   }
 
   .mdc-floating-label {
-    @include mdc-rtl-reflexive-position(left, 1px);
     @include mdc-floating-label-fill-color($mdc-textarea-background);
-
+    @include mdc-rtl-reflexive(left, 1px, right, 0);
+    @include mdc-rtl-reflexive-property(margin, 8px, 0);
+
     top: $label-offset-y;
     bottom: auto;
     margin-top: 2px;
-    margin-left: 8px;
-    padding: 8px;
+    padding: 12px 8px 8px 8px;
     line-height: 1.15;
+    pointer-events: none;
   }
 }