Store return types of variable initializers in summaries.

pkg/analyzer/lib/src/summary/format.dart

Index: pkg/analyzer/lib/src/summary/format.dart
diff --git a/pkg/analyzer/lib/src/summary/format.dart b/pkg/analyzer/lib/src/summary/format.dart
index bb93b483036065c7cc23d6c1701cc820afb6db77..7ffdf441c4ce8c5c7c3b6bc5ad9ef34b0b5acb18 100644
--- a/pkg/analyzer/lib/src/summary/format.dart
+++ b/pkg/analyzer/lib/src/summary/format.dart
@@ -2671,7 +2671,10 @@ class UnlinkedExecutableBuilder extends Object with _UnlinkedExecutableMixin imp
 
   /**
    * Declared return type of the executable.  Absent if the executable is a
-   * constructor or the return type is implicit.
+   * constructor or the return type is implicit.  Absent for executables
+   * associated with variable initializers and closures, since these
+   * executables may have return types that are not accessible via direct
+   * imports.
    */
   void set returnType(EntityRefBuilder _value) {
     assert(!_finished);
@@ -4369,6 +4372,7 @@ class UnlinkedReferenceBuilder extends Object with _UnlinkedReferenceMixin imple
   /**
    * Name of the entity being referred to.  For the pseudo-type `dynamic`, the
    * string is "dynamic".  For the pseudo-type `void`, the string is "void".
+   * For the pseudo-type `bottom`, the string is "*bottom*".
    */
   void set name(String _value) {
     assert(!_finished);