Minor type inference fixes.

pkg/analyzer/test/src/context/mock_sdk.dart

Index: pkg/analyzer/test/src/context/mock_sdk.dart
diff --git a/pkg/analyzer/test/src/context/mock_sdk.dart b/pkg/analyzer/test/src/context/mock_sdk.dart
index c7fa7c7767580ca2f33582f7463a5ddf3b9e3cd0..967ffb57bec8f9a835d8754a8b81929ef20dcc0b 100644
--- a/pkg/analyzer/test/src/context/mock_sdk.dart
+++ b/pkg/analyzer/test/src/context/mock_sdk.dart
@@ -167,6 +167,7 @@ class bool extends Object {
 abstract class Invocation {}
 
 abstract class num implements Comparable<num> {
+  bool operator ==(Object other);
   bool operator <(num other);
   bool operator <=(num other);
   bool operator >(num other);
@@ -268,6 +269,8 @@ abstract class Iterable<E> {
 
   Iterable/*<T>*/ expand/*<T>*/(Iterable/*<T>*/ f(E element));
 
+  Iterable<E> where(bool test(E element));
+
   List<E> toList();
 }