Remove deprecated_internalProblem.

pkg/front_end/lib/src/fasta/source/source_class_builder.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library fasta.source_class_builder;
 
-import 'package:front_end/src/fasta/builder/class_builder.dart'
-    show ClassBuilder;
-
-import 'package:front_end/src/fasta/source/source_library_builder.dart'
-    show SourceLibraryBuilder;
-
 import 'package:kernel/ast.dart'
     show Class, Constructor, Supertype, TreeNode, setParents;
 
-import '../deprecated_problems.dart' show deprecated_internalProblem;
+import '../dill/dill_member_builder.dart' show DillMemberBuilder;
 
 import '../kernel/kernel_builder.dart'
     show
         Builder,
+        ClassBuilder,
         ConstructorReferenceBuilder,
         KernelClassBuilder,
         KernelFieldBuilder,
         KernelFunctionBuilder,
         KernelLibraryBuilder,
         KernelTypeBuilder,
         KernelTypeVariableBuilder,
         LibraryBuilder,
         MetadataBuilder,
         Scope,
         TypeVariableBuilder,
         compareProcedures;
 
-import '../dill/dill_member_builder.dart' show DillMemberBuilder;
+import '../problems.dart' show unhandled;
+
+import 'source_library_builder.dart' show SourceLibraryBuilder;
 
 Class initializeClass(
     Class cls, String name, KernelLibraryBuilder parent, int charOffset) {
   cls ??= new Class(name: name);
   cls.fileUri ??= parent.library.fileUri;
   if (cls.fileOffset == TreeNode.noOffset) {
     cls.fileOffset = charOffset;
   }
   return cls;
 }
@@ skipping 39 matching lines @@
   Class build(KernelLibraryBuilder library, LibraryBuilder coreLibrary) {
     void buildBuilders(String name, Builder builder) {
       do {
         if (builder is KernelFieldBuilder) {
           // TODO(ahe): It would be nice to have a common interface for the
           // build method to avoid duplicating these two cases.
           cls.addMember(builder.build(library));
         } else if (builder is KernelFunctionBuilder) {
           cls.addMember(builder.build(library));
         } else {
-          deprecated_internalProblem(
-              "Unhandled builder: ${builder.runtimeType}");
+          unhandled("${builder.runtimeType}", "buildBuilders",
+              builder.charOffset, builder.fileUri);
         }
         builder = builder.next;
       } while (builder != null);
     }
 
     scope.forEach(buildBuilders);
     constructors.forEach(buildBuilders);
     cls.supertype = supertype?.buildSupertype(library);
     cls.mixedInType = mixedInType?.buildSupertype(library);
     // TODO(ahe): If `cls.supertype` is null, and this isn't Object, report a
@@ skipping 49 matching lines @@
   }
 
   @override
   void prepareInitializerInference(
       SourceLibraryBuilder library, ClassBuilder currentClass) {
     scope.forEach((name, builder) {
       builder.prepareInitializerInference(library, this);
     });
   }
 }