Adjust Material 3 textfield padding to align with specs (#116225)

* Adjust textfield padding

* lint

* lint

Author: hannah-hyj

packages/flutter/lib/src/material/input_decorator.dart

@@ -2345,18 +2345,14 @@ class _InputDecoratorState extends State<InputDecorator> with TickerProviderStat
       if (decoration.filled ?? false) {
         contentPadding = decorationContentPadding ?? (decorationIsDense
           ? const EdgeInsets.fromLTRB(12.0, 8.0, 12.0, 8.0)
-          : themeData.useMaterial3
-            ? const EdgeInsets.fromLTRB(12.0, 12.75, 12.0, 12.75)
-            : const EdgeInsets.fromLTRB(12.0, 12.0, 12.0, 12.0));
+          : const EdgeInsets.fromLTRB(12.0, 12.0, 12.0, 12.0));
       } else {
         // Not left or right padding for underline borders that aren't filled
         // is a small concession to backwards compatibility. This eliminates
         // the most noticeable layout change introduced by #13734.
         contentPadding = decorationContentPadding ?? (decorationIsDense
           ? const EdgeInsets.fromLTRB(0.0, 8.0, 0.0, 8.0)
-          : themeData.useMaterial3
-            ? const EdgeInsets.fromLTRB(0.0, 12.75, 0.0, 12.75)
-            : const EdgeInsets.fromLTRB(0.0, 12.0, 0.0, 12.0));
+          : const EdgeInsets.fromLTRB(0.0, 12.0, 0.0, 12.0));
       }
     } else {
       floatingLabelHeight = 0.0;