Add top level type inference logic for integer literals.

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

Index: pkg/front_end/lib/src/fasta/source/source_library_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
index 8c552e4db4346458578408dd758395361e4e552b..3a0985fd7039b44a01d49d6bf507669a71f3ea05 100644
--- a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
@@ -4,6 +4,11 @@
 
 library fasta.source_library_builder;
 
+import 'package:front_end/src/fasta/scanner/token.dart' show SymbolToken, Token;
+
+import 'package:front_end/src/fasta/type_inference/type_inferrer.dart'
+    show TypeInferrer;
+
 import 'package:kernel/ast.dart' show AsyncMarker, ProcedureKind;
 
 import '../combinator.dart' show Combinator;
@@ -171,14 +176,23 @@ abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
       int charOffset);
 
   void addField(List<MetadataBuilder> metadata, int modifiers, T type,
-      String name, int charOffset);
+      String name, int charOffset, Token initializer);
 
   void addFields(List<MetadataBuilder> metadata, int modifiers, T type,
-      List<Object> namesAndOffsets) {
-    for (int i = 0; i < namesAndOffsets.length; i += 2) {
-      String name = namesAndOffsets[i];
-      int charOffset = namesAndOffsets[i + 1];
-      addField(metadata, modifiers, type, name, charOffset);
+      List<Object> namesOffsetsAndInitializers) {
+    for (int i = 0; i < namesOffsetsAndInitializers.length; i += 4) {
+      String name = namesOffsetsAndInitializers[i];
+      int charOffset = namesOffsetsAndInitializers[i + 1];
+      Token initializer;
+      if (type == null) {
+        initializer = namesOffsetsAndInitializers[i + 2];
+        Token afterInitializer = namesOffsetsAndInitializers[i + 3];
+        // TODO(paulberry): figure out a way to do this without using
+        // Token.previous.
+        afterInitializer?.previous
+            ?.setNext(new SymbolToken.eof(afterInitializer.offset));
+      }
+      addField(metadata, modifiers, type, name, charOffset, initializer);
     }
   }
 
@@ -469,6 +483,14 @@ abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
 
   @override
   String get fullNameForErrors => name ?? "<library '$relativeFileUri'>";
+
+  @override
+  void prepareInitializerInference(TypeInferrer typeInferrer,
+      LibraryBuilder library, ClassBuilder currentClass) {
+    forEach((String name, Builder member) {
+      member.prepareInitializerInference(typeInferrer, library, currentClass);
+    });
+  }
 }
 
 /// Unlike [Scope], this scope is used during construction of builders to