Remove ElementType.canHaveParameters; unused (#3563)

Author: srawlins

lib/src/element_type.dart

@@ -57,8 +57,6 @@ abstract class ElementType
     return DefinedElementType._from(type, modelElement, library, packageGraph);
   }
 
-  bool get canHaveParameters => false;
-
   bool get isTypedef => false;
 
   String get linkedName;

lib/src/generator/templates.runtime_renderers.dart

@@ -4399,13 +4399,6 @@ class _Renderer_ElementType extends RendererBase<ElementType> {
                 ..._Renderer_CommentReferable.propertyMap<CT_>(),
                 ..._Renderer_Nameable.propertyMap<CT_>(),
                 ..._Renderer_ModelBuilder.propertyMap<CT_>(),
-                'canHaveParameters': Property(
-                  getValue: (CT_ c) => c.canHaveParameters,
-                  renderVariable: (CT_ c, Property<CT_> self,
-                          List<String> remainingNames) =>
-                      self.renderSimpleVariable(c, remainingNames, 'bool'),
-                  getBool: (CT_ c) => c.canHaveParameters == true,
-                ),
                 'instantiatedType': Property(
                   getValue: (CT_ c) => c.instantiatedType,
                   renderVariable: (CT_ c, Property<CT_> self,