Add import/export declaration AST node boilerplate to kernel.

pkg/analyzer/lib/src/kernel/loader.dart

Index: pkg/analyzer/lib/src/kernel/loader.dart
diff --git a/pkg/analyzer/lib/src/kernel/loader.dart b/pkg/analyzer/lib/src/kernel/loader.dart
index 351e7331145da4f1409134120f0d571b53bcd101..ce18e6ea0153550208bf3c6da3ebbe2bcf0c409f 100644
--- a/pkg/analyzer/lib/src/kernel/loader.dart
+++ b/pkg/analyzer/lib/src/kernel/loader.dart
@@ -702,6 +702,20 @@ class DartLoader implements ReferenceLevelLoader {
       units.add(context.resolveCompilationUnit(source, element));
       if (reportErrors) _processErrors(source);
     }
+    for (var import in element.imports) {
+      if (import.isDeferred && import.prefix != null) {
+        node.addDependency(new ast.LibraryDependency.deferredImport(
+            getLibraryReference(import.importedLibrary), import.prefix.name));
+      } else {
+        node.addDependency(new ast.LibraryDependency.import(
+            getLibraryReference(import.importedLibrary),
+            name: import.prefix?.name));
+      }
+    }
+    for (var export in element.exports) {
+      node.addDependency(new ast.LibraryDependency.export(
+          getLibraryReference(export.exportedLibrary)));
+    }
     _buildLibraryBody(element, node, units);
   }