Support for Int64 and fix for the root reference.

pkg/analyzer/test/src/summary/flat_buffers_test.dart

Index: pkg/analyzer/test/src/summary/flat_buffers_test.dart
diff --git a/pkg/analyzer/test/src/summary/flat_buffers_test.dart b/pkg/analyzer/test/src/summary/flat_buffers_test.dart
index 4f46528817993db051d71b26fd4645231188a0a3..a15f31ef14fdf8cfa300f1db7901db1a29b2b99a 100644
--- a/pkg/analyzer/test/src/summary/flat_buffers_test.dart
+++ b/pkg/analyzer/test/src/summary/flat_buffers_test.dart
@@ -86,6 +86,28 @@ class BuilderTest {
     expect(const Int32Reader().vTableGet(object, 1, 15), 20);
   }
 
+  void test_table_int64() {
+    List<int> byteList;
+    {
+      Builder builder = new Builder(initialSize: 0);
+      builder.startTable();
+      builder.addInt8(0, 10);
+      builder.addInt64(1, 20);
+      builder.addInt8(2, 30);
+      builder.addInt8(3, 40);
+      builder.addInt8(4, 50);
+      Offset offset = builder.endTable();
+      byteList = builder.finish(offset);
+    }
+    // read and verify
+    BufferPointer object = new BufferPointer.fromBytes(byteList).derefObject();
+    expect(const Int8Reader().vTableGet(object, 0), 10);
+    expect(const Int64Reader().vTableGet(object, 1), 20);
+    expect(const Int8Reader().vTableGet(object, 2), 30);
+    expect(const Int8Reader().vTableGet(object, 3), 40);
+    expect(const Int8Reader().vTableGet(object, 4), 50);
+  }
+
   void test_table_types() {
     List<int> byteList;
     {