diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 9de448f4236..e90e40967d3 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -83,13 +83,10 @@ namespace ts {
             getSignaturesOfType,
             getIndexTypeOfType,
             getBaseTypes,
-            getUnionType,
-            getIntersectionType,
-            getTypeFromTypeReference,
+            getTypeFromTypeNode,
             getReturnTypeOfSignature,
             getNonNullableType,
             getSymbolsInScope,
-            createSymbol,
             getSymbolAtLocation,
             getShorthandAssignmentValueSymbol,
             getExportSpecifierLocalTargetSymbol,
@@ -19743,9 +19740,6 @@ namespace ts {
                 // This is a declaration, call getSymbolOfNode
                 return getSymbolOfNode(node.parent);
             }
-            else if (node.kind === SyntaxKind.ClassKeyword && node.parent.kind === SyntaxKind.ClassExpression) {
-                return getSymbolOfNode(node.parent);
-            }
             else if (isLiteralComputedPropertyDeclarationName(node)) {
                 return getSymbolOfNode(node.parent.parent);
             }
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index a6f40041f3c..a9faae5004e 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -3203,10 +3203,6 @@
         "category": "Message",
         "code": 90004
     },
-    "Implement interface on reference": {
-        "category": "Message",
-        "code": 90005
-    },
     "Implement interface '{0}'.": {
         "category": "Message",
         "code": 90006
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 2a04916d45d..e035b4d3919 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -2341,8 +2341,6 @@ namespace ts {
         getBaseTypes(type: InterfaceType): ObjectType[];
         getReturnTypeOfSignature(signature: Signature): Type;
         getNonNullableType(type: Type): Type;
-        getIntersectionType(types: Type[], aliasSymbol?: Symbol, aliasTypeArguments?: Type[]): Type;
-        getUnionType(types: Type[], subtypeReduction?: boolean, aliasSymbol?: Symbol, aliasTypeArguments?: Type[]): Type;
 
         getSymbolsInScope(location: Node, meaning: SymbolFlags): Symbol[];
         getSymbolAtLocation(node: Node): Symbol;
@@ -2351,11 +2349,10 @@ namespace ts {
         getExportSpecifierLocalTargetSymbol(location: ExportSpecifier): Symbol;
         getPropertySymbolOfDestructuringAssignment(location: Identifier): Symbol;
         getTypeAtLocation(node: Node): Type;
-        getTypeFromTypeReference(node: TypeReferenceNode | ExpressionWithTypeArguments | JSDocTypeReference): Type;
+        getTypeFromTypeNode(node: TypeNode): Type;
         signatureToString(signature: Signature, enclosingDeclaration?: Node, flags?: TypeFormatFlags, kind?: SignatureKind): string;
         typeToString(type: Type, enclosingDeclaration?: Node, flags?: TypeFormatFlags): string;
         symbolToString(symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags): string;
-        createSymbol(flags: SymbolFlags, name: string): Symbol;
         getSymbolDisplayBuilder(): SymbolDisplayBuilder;
         getFullyQualifiedName(symbol: Symbol): string;
         getAugmentedPropertiesOfType(type: Type): Symbol[];
diff --git a/src/services/codefixes/fixClassIncorrectlyImplementsInterface.ts b/src/services/codefixes/fixClassIncorrectlyImplementsInterface.ts
index 915b23f050b..42488dc2aed 100644
--- a/src/services/codefixes/fixClassIncorrectlyImplementsInterface.ts
+++ b/src/services/codefixes/fixClassIncorrectlyImplementsInterface.ts
@@ -25,7 +25,7 @@ namespace ts.codefix {
 
         const result: CodeAction[] = [];
         for (const implementedTypeNode of implementedTypeNodes) {
-            const implementedType = checker.getTypeFromTypeReference(implementedTypeNode) as InterfaceType;
+            const implementedType = checker.getTypeFromTypeNode(implementedTypeNode) as InterfaceType;
             // Note that this is ultimately derived from a map indexed by symbol names,
             // so duplicates cannot occur.
             const implementedTypeSymbols = checker.getPropertiesOfType(implementedType);
diff --git a/src/services/codefixes/helpers.ts b/src/services/codefixes/helpers.ts
index 9827ec14f3b..d539ef0d68b 100644
--- a/src/services/codefixes/helpers.ts
+++ b/src/services/codefixes/helpers.ts
@@ -87,7 +87,6 @@ namespace ts.codefix {
     }
 
     function createBodySignatureWithAnyTypes(signatures: Signature[], enclosingDeclaration: ClassLikeDeclaration, checker: TypeChecker): Signature {
-
         const newSignatureDeclaration = createNode(SyntaxKind.CallSignature) as SignatureDeclaration;
         newSignatureDeclaration.parent = enclosingDeclaration;
         newSignatureDeclaration.name = signatures[0].getDeclaration().name;
@@ -126,7 +125,8 @@ namespace ts.codefix {
 
         function createParameterDeclarationWithoutType(index: number, minArgCount: number, enclosingSignatureDeclaration: SignatureDeclaration): ParameterDeclaration {
             const newParameter = createNode(SyntaxKind.Parameter) as ParameterDeclaration;
-            newParameter.symbol = checker.createSymbol(SymbolFlags.FunctionScopedVariable, maxArgsParameterSymbolNames[index] || "rest");
+
+            newParameter.symbol = new SymbolConstructor(SymbolFlags.FunctionScopedVariable, maxArgsParameterSymbolNames[index] || "rest");
             newParameter.symbol.valueDeclaration = newParameter;
             newParameter.symbol.declarations = [newParameter];
             newParameter.parent = enclosingSignatureDeclaration;
@@ -151,4 +151,6 @@ namespace ts.codefix {
         }
         return "";
     }
+
+    const SymbolConstructor = objectAllocator.getSymbolConstructor();
 }
\ No newline at end of file