[TextInputLayout] Fixed regression bug of prefix spacing being shown …

…and making expanded label be in the wrong position when text field is not focused.

Resolves #2612

PiperOrigin-RevId: 437745108
(cherry picked from commit 784f901)

lib/java/com/google/android/material/textfield/TextInputLayout.java

@@ -3995,7 +3995,8 @@ boolean updateDummyDrawables() {
   }
 
   private boolean shouldUpdateStartDummyDrawable() {
-    return (getStartIconDrawable() != null || getPrefixText() != null)
+    return (getStartIconDrawable() != null
+            || (getPrefixText() != null && getPrefixTextView().getVisibility() == VISIBLE))
         && (startLayout.getMeasuredWidth() > 0);
   }