fix string interpolation $

com.unity.uiwidgets/Runtime/animation/tween_sequence.cs

               if (_intervals[index].contains(t))
                 return _evaluateAt(t, index);
             }
-            D.assert(false, ()=>"TweenSequence.evaluate() could not find an interval for $t");
+            D.assert(false, ()=>$"TweenSequence.evaluate() could not find an interval for {t}");
             return default(T);
         }
         public override string ToString(){

com.unity.uiwidgets/Runtime/painting/inline_span.cs

 
         public override string ToString() =>
             $"{foundation_.objectRuntimeType(this, "InlineSpanSemanticsInformation")}" +
-            $"{text: $text, semanticsLabel: $semanticsLabel, recognizer: $recognizer}";
+            "text: " + text + " , semanticsLabel: "+ semanticsLabel + " , recognizer: " + recognizer;
 
         public bool Equals(InlineSpanSemanticsInformation other) {
             if (ReferenceEquals(null, other)) {

com.unity.uiwidgets/Runtime/rendering/view.cs

         }
 
         public override string ToString() {
-            return $"${size} at ${devicePixelRatio}x";
+            return $"{size} at {devicePixelRatio}x";
         }
     }
 

com.unity.uiwidgets/Runtime/service/text_input.cs

                     return TextInputAction.newline;
             }
 
-            throw new UIWidgetsError("Unknown text input action: $action");
+            throw new UIWidgetsError($"Unknown text input action: {action}");
         }
 
         public static FloatingCursorDragState _toTextCursorAction(string state) {
                     return FloatingCursorDragState.End;
             }
 
-            throw new UIWidgetsError("Unknown text cursor action: $state");
+            throw new UIWidgetsError($"Unknown text cursor action: {state}");
         }
 
         public static RawFloatingCursorPoint _toTextPoint(FloatingCursorDragState state,

com.unity.uiwidgets/Runtime/widgets/focus_manager.cs

             D.assert(findFirstFocus != null);
             if (!canRequestFocus) {
                 D.assert(FocusManagerUtils._focusDebug(
-                    "Node NOT requesting focus because canRequestFocus is false: $this"));
+                    $"Node NOT requesting focus because canRequestFocus is false: {this}"));
                 return;
             }
 
         public void setFirstFocus(FocusScopeNode scope) {
             D.assert(scope != null);
             D.assert(scope != this, ()=>"Unexpected self-reference in setFirstFocus.");
-            D.assert(FocusManagerUtils._focusDebug("Setting scope as first focus in $this to node:", new List<string>{scope.ToString()}));
+            D.assert(FocusManagerUtils._focusDebug($"Setting scope as first focus in {this} to node:", new List<string>{scope.ToString()}));
             if (scope._parent == null) {
               _reparent(scope);
             }
         }
 
         public void autofocus(FocusNode node) { 
-        D.assert(FocusManagerUtils._focusDebug("Node autofocusing: $node"));
+        D.assert(FocusManagerUtils._focusDebug($"Node autofocusing: {node}"));
             if (focusedChild == null) {
               if (node._parent == null) {
                 _reparent(node);

com.unity.uiwidgets/Runtime/widgets/gesture_detector.cs

 
         internal override bool _debugAssertTypeMatches(Type type) {
             D.assert(type == typeof(T),
-                () => "GestureRecognizerFactory of type " + typeof(T) + " was used where type $type was specified.");
+                () => "GestureRecognizerFactory of type " + typeof(T) + $" was used where type {type} was specified.");
             return true;
         }
     }

com.unity.uiwidgets/Runtime/widgets/widget_inspector.cs

                             name: "The relevant error-causing widget was",
                             children: new List<DiagnosticsNode>() {
                                 new ErrorDescription(
-                                    "${target.widget.toStringShort()} ${_describeCreationLocation(target)}"),
+                                    $"{target.widget.toStringShort()} " + $"{_describeCreationLocation(target)}"),
                             }
                         ));
                     nodes.Add(new ErrorSpacer());
             if (file != null) {
                 parts.Add(file);
             }
-            parts.Add("$line");
-            parts.Add("$column");
+            parts.Add($"{line}");
+            parts.Add($"{column}");
             string result = "";
             foreach (var part in parts) {
                 result += part;