dart2js: Move TypeTestRegistry into its own file.

pkg/compiler/lib/src/js_emitter/old_emitter/type_test_emitter.dart

Index: pkg/compiler/lib/src/js_emitter/old_emitter/type_test_emitter.dart
diff --git a/pkg/compiler/lib/src/js_emitter/old_emitter/type_test_emitter.dart b/pkg/compiler/lib/src/js_emitter/old_emitter/type_test_emitter.dart
index 26af03df262d2647310093d729b16a3ceb2dc819..bb6b74328a56aa9ab28995a47982b8a01ee01e5a 100644
--- a/pkg/compiler/lib/src/js_emitter/old_emitter/type_test_emitter.dart
+++ b/pkg/compiler/lib/src/js_emitter/old_emitter/type_test_emitter.dart
@@ -4,164 +4,6 @@
 
 part of dart2js.js_emitter;
 
-class TypeTestRegistry {
-  /**
-   * Raw ClassElement symbols occuring in is-checks and type assertions.  If the
-   * program contains parameterized checks `x is Set<int>` and
-   * `x is Set<String>` then the ClassElement `Set` will occur once in
-   * [checkedClasses].
-   */
-  Set<ClassElement> checkedClasses;
-
-  /**
-   * The set of function types that checked, both explicity through tests of
-   * typedefs and implicitly through type annotations in checked mode.
-   */
-  Set<FunctionType> checkedFunctionTypes;
-
-  /// Initially contains all classes that need RTI. After
-  /// [computeNeededClasses]
-  /// this set only contains classes that are only used for RTI.
-  final Set<ClassElement> rtiNeededClasses = new Set<ClassElement>();
-
-  Iterable<ClassElement> cachedClassesUsingTypeVariableTests;
-
-  Iterable<ClassElement> get classesUsingTypeVariableTests {
-    if (cachedClassesUsingTypeVariableTests == null) {
-      cachedClassesUsingTypeVariableTests = compiler.codegenWorld.isChecks
-          .where((DartType t) => t is TypeVariableType)
-          .map((TypeVariableType v) => v.element.enclosingClass)
-          .toList();
-    }
-    return cachedClassesUsingTypeVariableTests;
-  }
-
-  final Compiler compiler;
-
-  TypeTestRegistry(this.compiler);
-
-  JavaScriptBackend get backend => compiler.backend;
-
-  /**
-   * Returns the classes with constructors used as a 'holder' in
-   * [emitRuntimeTypeSupport].
-   * TODO(9556): Some cases will go away when the class objects are created as
-   * complete.  Not all classes will go away while constructors are referenced
-   * from type substitutions.
-   */
-  Set<ClassElement> classesModifiedByEmitRuntimeTypeSupport() {
-    TypeChecks typeChecks = backend.rti.requiredChecks;
-    Set<ClassElement> result = new Set<ClassElement>();
-    for (ClassElement cls in typeChecks) {
-      for (TypeCheck check in typeChecks[cls]) {
-        result.add(cls);
-        break;
-      }
-    }
-    return result;
-  }
-
-  Set<ClassElement> computeRtiNeededClasses() {
-    void addClassWithSuperclasses(ClassElement cls) {
-      rtiNeededClasses.add(cls);
-      for (ClassElement superclass = cls.superclass;
-          superclass != null;
-          superclass = superclass.superclass) {
-        rtiNeededClasses.add(superclass);
-      }
-    }
-
-    void addClassesWithSuperclasses(Iterable<ClassElement> classes) {
-      for (ClassElement cls in classes) {
-        addClassWithSuperclasses(cls);
-      }
-    }
-
-    // 1.  Add classes that are referenced by type arguments or substitutions in
-    //     argument checks.
-    // TODO(karlklose): merge this case with 2 when unifying argument and
-    // object checks.
-    RuntimeTypes rti = backend.rti;
-    rti.getRequiredArgumentClasses(backend)
-       .forEach(addClassWithSuperclasses);
-
-    // 2.  Add classes that are referenced by substitutions in object checks and
-    //     their superclasses.
-    TypeChecks requiredChecks =
-        rti.computeChecks(rtiNeededClasses, checkedClasses);
-    Set<ClassElement> classesUsedInSubstitutions =
-        rti.getClassesUsedInSubstitutions(backend, requiredChecks);
-    addClassesWithSuperclasses(classesUsedInSubstitutions);
-
-    // 3.  Add classes that contain checked generic function types. These are
-    //     needed to store the signature encoding.
-    for (FunctionType type in checkedFunctionTypes) {
-      ClassElement contextClass = Types.getClassContext(type);
-      if (contextClass != null) {
-        rtiNeededClasses.add(contextClass);
-      }
-    }
-
-    bool canTearOff(Element function) {
-      if (!function.isFunction ||
-          function.isConstructor ||
-          function.isAccessor) {
-        return false;
-      } else if (function.isInstanceMember) {
-        if (!function.enclosingClass.isClosure) {
-          return compiler.codegenWorld.hasInvokedGetter(
-              function, compiler.world);
-        }
-      }
-      return false;
-    }
-
-    bool canBeReflectedAsFunction(Element element) {
-      return element.kind == ElementKind.FUNCTION ||
-          element.kind == ElementKind.GETTER ||
-          element.kind == ElementKind.SETTER ||
-          element.kind == ElementKind.GENERATIVE_CONSTRUCTOR;
-    }
-
-    bool canBeReified(Element element) {
-      return (canTearOff(element) || backend.isAccessibleByReflection(element));
-    }
-
-    // Find all types referenced from the types of elements that can be
-    // reflected on 'as functions'.
-    backend.generatedCode.keys.where((element) {
-      return canBeReflectedAsFunction(element) && canBeReified(element);
-    }).forEach((FunctionElement function) {
-      DartType type = function.computeType(compiler);
-      for (ClassElement cls in backend.rti.getReferencedClasses(type)) {
-        while (cls != null) {
-          rtiNeededClasses.add(cls);
-          cls = cls.superclass;
-        }
-      }
-    });
-
-    return rtiNeededClasses;
-  }
-
-  void computeRequiredTypeChecks() {
-    assert(checkedClasses == null && checkedFunctionTypes == null);
-
-    backend.rti.addImplicitChecks(compiler.codegenWorld,
-                                  classesUsingTypeVariableTests);
-
-    checkedClasses = new Set<ClassElement>();
-    checkedFunctionTypes = new Set<FunctionType>();
-    compiler.codegenWorld.isChecks.forEach((DartType t) {
-      if (t is InterfaceType) {
-        checkedClasses.add(t.element);
-      } else if (t is FunctionType) {
-        checkedFunctionTypes.add(t);
-      }
-    });
-  }
-}
-
 class TypeTestEmitter extends CodeEmitterHelper {
   Set<ClassElement> get checkedClasses =>
       emitter.typeTestRegistry.checkedClasses;