Move the filterNonDocumented and filterNonPublic functions as ext…

…ension getters (#3699)

`filterNonPublic` becomes an extension getter, `wherePublic`, and
`filterNonDocumented` becomes an extension getter, `whereDocumented`.

Nameable now implements Privacy. Privacy is now an abstract interface class.

Changing all the call sites highlights a number of ModelElement getters that
are superfluous. For example, `Container.publicInstanceMethods`. This was a
getter that now boils down to `instanceMethods.wherePublic`, and it really is
unneccessary to keep this; there are many such methods that are removed here:

* Container: `publicInstanceMethods`, `publicInstanceOperators`, `publicInstanceFields`,
  `publicConstantFields`,
* InheritingContainer: `publicSuperChain`, `publicInheritedFields`, `publicInheritedMethods`,
* LibraryContainer: `publicLibraries`,
* Package: `documentedCategories`,
* PackageGraph: `documentedExtensions`,
* TopLevelContainer: `publicClasses`, `publicExtensions`,
  `publicExtensionTypes`, `publicConstants`, `publicEnums`,
  `_publicExceptions`, `publicFunctions`, `publicMixins`, `publicProperties`,
  `publicTypedefs`.

Additionally, this change highlights some small inefficiency in some `hasX`
methods. For example, `hasPublicInstanceMethods` used to enumerate all of the
public instance methods, then ask if the list is empty. Now we can ask if `any`
of the `instanceMethods` are `public`.

* Container: `hasPublicInstanceMethods`, `hasPublicInstanceOperators`,
  `hasPublicInstanceFields`, `hasPublicConstantFields`,
  `hasPublicVariableStaticFields`, `hasPublicStaticMethods`,
  `hasPublicEnumValues`,
* InheritingContainer: `hasPublicInheritedMethods`,
  `hasPublicSuperChainReversed`,
* MixedInTypes: `hasPublicMixedInTypes`,
* LibraryContainer: `hasPublicLibraries`,
* Package: `hasDocumentedCategories`,
* TopLevelContainer: `hasPublicClasses`, `hasPublicExtensions`,
  `hasPublicExtensionTypes`, `hasPublicConstants`, `hasPublicEnums`,
  `hasPublicExceptions`, `hasPublicFunctions`,`hasPublicMixins`,
  `hasPublicProperties`, `hasPublicTypedefs`.

Because the field `InheritingContaier.publicSuperChain` is removed, I change
`superChain` from a getter to a field, sort of the point of caching.

lib/src/generator/empty_generator.dart

@@ -18,13 +18,14 @@ class EmptyGenerator implements Generator {
       packageGraph.defaultPackage,
       ...packageGraph.localPackages
     }) {
-      for (var category in filterNonDocumented(package.categories)) {
+      for (var category in package.categories.whereDocumented) {
         logProgress(category.documentationAsHtml);
       }
 
-      for (var lib in filterNonDocumented(package.libraries)) {
-        filterNonDocumented(lib.allModelElements)
-            .forEach((m) => logProgress(m.documentationAsHtml));
+      for (var lib in package.libraries.whereDocumented) {
+        for (var e in lib.allModelElements.whereDocumented) {
+          logProgress(e.documentationAsHtml);
+        }
       }
     }
     return Future.value();

lib/src/generator/generator_frontend.dart

@@ -79,7 +79,7 @@ class GeneratorFrontEnd implements Generator {
     var multiplePackages = packageGraph.localPackages.length > 1;
 
     void generateConstants(Container container) {
-      for (var constant in filterNonDocumented(container.constantFields)) {
+      for (var constant in container.constantFields.whereDocumented) {
         if (!constant.isCanonical) continue;
         indexAccumulator.add(constant);
         _generatorBackend.generateProperty(
@@ -88,7 +88,7 @@ class GeneratorFrontEnd implements Generator {
     }
 
     void generateConstructors(Constructable constructable) {
-      for (var constructor in filterNonDocumented(constructable.constructors)) {
+      for (var constructor in constructable.constructors.whereDocumented) {
         if (!constructor.isCanonical) continue;
         indexAccumulator.add(constructor);
         _generatorBackend.generateConstructor(
@@ -97,7 +97,7 @@ class GeneratorFrontEnd implements Generator {
     }
 
     void generateInstanceMethods(Container container) {
-      for (var method in filterNonDocumented(container.instanceMethods)) {
+      for (var method in container.instanceMethods.whereDocumented) {
         if (!method.isCanonical) continue;
         indexAccumulator.add(method);
         _generatorBackend.generateMethod(
@@ -106,7 +106,7 @@ class GeneratorFrontEnd implements Generator {
     }
 
     void generateInstanceOperators(Container container) {
-      for (var operator in filterNonDocumented(container.instanceOperators)) {
+      for (var operator in container.instanceOperators.whereDocumented) {
         if (!operator.isCanonical) continue;
         indexAccumulator.add(operator);
         _generatorBackend.generateMethod(
@@ -115,7 +115,7 @@ class GeneratorFrontEnd implements Generator {
     }
 
     void generateInstanceProperty(Container container) {
-      for (var property in filterNonDocumented(container.instanceFields)) {
+      for (var property in container.instanceFields.whereDocumented) {
         if (!property.isCanonical) continue;
         indexAccumulator.add(property);
         _generatorBackend.generateProperty(
@@ -124,7 +124,7 @@ class GeneratorFrontEnd implements Generator {
     }
 
     void generateStaticMethods(Container container) {
-      for (var method in filterNonDocumented(container.staticMethods)) {
+      for (var method in container.staticMethods.whereDocumented) {
         if (!method.isCanonical) continue;
         indexAccumulator.add(method);
         _generatorBackend.generateMethod(
@@ -133,8 +133,7 @@ class GeneratorFrontEnd implements Generator {
     }
 
     void generateStaticProperty(Container container) {
-      for (var property
-          in filterNonDocumented(container.variableStaticFields)) {
+      for (var property in container.variableStaticFields.whereDocumented) {
         if (!property.isCanonical) continue;
         indexAccumulator.add(property);
         _generatorBackend.generateProperty(
@@ -146,14 +145,14 @@ class GeneratorFrontEnd implements Generator {
       if (multiplePackages) {
         logInfo('Generating docs for package ${package.name}...');
       }
-      for (var category in filterNonDocumented(package.categories)) {
+      for (var category in package.categories.whereDocumented) {
         logInfo('Generating docs for category ${category.name} from '
             '${category.package.fullyQualifiedName}...');
         indexAccumulator.add(category);
         _generatorBackend.generateCategory(packageGraph, category);
       }
 
-      for (var lib in filterNonDocumented(package.libraries)) {
+      for (var lib in package.libraries.whereDocumented) {
         if (!multiplePackages) {
           logInfo('Generating docs for library ${lib.breadcrumbName} from '
               '${lib.element.source.uri}...');
@@ -164,7 +163,7 @@ class GeneratorFrontEnd implements Generator {
         indexAccumulator.add(lib);
         _generatorBackend.generateLibrary(packageGraph, lib);
 
-        for (var class_ in filterNonDocumented(lib.allClasses)) {
+        for (var class_ in lib.allClasses.whereDocumented) {
           indexAccumulator.add(class_);
           _generatorBackend.generateClass(packageGraph, lib, class_);
 
@@ -177,7 +176,7 @@ class GeneratorFrontEnd implements Generator {
           generateStaticProperty(class_);
         }
 
-        for (var extension in filterNonDocumented(lib.extensions)) {
+        for (var extension in lib.extensions.whereDocumented) {
           indexAccumulator.add(extension);
           _generatorBackend.generateExtension(packageGraph, lib, extension);
 
@@ -189,7 +188,7 @@ class GeneratorFrontEnd implements Generator {
           generateStaticProperty(extension);
         }
 
-        for (var extensionType in filterNonDocumented(lib.extensionTypes)) {
+        for (var extensionType in lib.extensionTypes.whereDocumented) {
           indexAccumulator.add(extensionType);
           _generatorBackend.generateExtensionType(
               packageGraph, lib, extensionType);
@@ -203,7 +202,7 @@ class GeneratorFrontEnd implements Generator {
           generateStaticProperty(extensionType);
         }
 
-        for (var mixin in filterNonDocumented(lib.mixins)) {
+        for (var mixin in lib.mixins.whereDocumented) {
           indexAccumulator.add(mixin);
           _generatorBackend.generateMixin(packageGraph, lib, mixin);
 
@@ -215,7 +214,7 @@ class GeneratorFrontEnd implements Generator {
           generateStaticProperty(mixin);
         }
 
-        for (var enum_ in filterNonDocumented(lib.enums)) {
+        for (var enum_ in lib.enums.whereDocumented) {
           indexAccumulator.add(enum_);
           _generatorBackend.generateEnum(packageGraph, lib, enum_);
 
@@ -228,24 +227,24 @@ class GeneratorFrontEnd implements Generator {
           generateStaticProperty(enum_);
         }
 
-        for (var constant in filterNonDocumented(lib.constants)) {
+        for (var constant in lib.constants.whereDocumented) {
           indexAccumulator.add(constant);
           _generatorBackend.generateTopLevelProperty(
               packageGraph, lib, constant);
         }
 
-        for (var property in filterNonDocumented(lib.properties)) {
+        for (var property in lib.properties.whereDocumented) {
           indexAccumulator.add(property);
           _generatorBackend.generateTopLevelProperty(
               packageGraph, lib, property);
         }
 
-        for (var function in filterNonDocumented(lib.functions)) {
+        for (var function in lib.functions.whereDocumented) {
           indexAccumulator.add(function);
           _generatorBackend.generateFunction(packageGraph, lib, function);
         }
 
-        for (var typeDef in filterNonDocumented(lib.typedefs)) {
+        for (var typeDef in lib.typedefs.whereDocumented) {
           indexAccumulator.add(typeDef);
           _generatorBackend.generateTypeDef(packageGraph, lib, typeDef);
         }

lib/src/generator/templates.aot_renderers_for_html.dart

@@ -1584,7 +1584,7 @@ String renderMixin(MixinTemplateData context0) {
       <h2>Properties</h2>
 
       <dl class="properties">''');
-    var context7 = context2.publicInstanceFields;
+    var context7 = context2.publicInstanceFieldsSorted;
     for (var context8 in context7) {
       buffer.write('\n          ');
       buffer.write(_renderMixin_partial_property_8(context8));