Revert "[kernel] Don't use kernel ast nodes as keys"

runtime/vm/kernel_to_il.h

Index: runtime/vm/kernel_to_il.h
diff --git a/runtime/vm/kernel_to_il.h b/runtime/vm/kernel_to_il.h
index 7d71ad21e544211cf4a2d4bc6ac0425812e1c768..e6033eb45cf6d2beee81da5201cb68ce1b3fba47 100644
--- a/runtime/vm/kernel_to_il.h
+++ b/runtime/vm/kernel_to_il.h
@@ -81,54 +81,6 @@ class Map : public DirectChainedHashMap<RawPointerKeyValueTrait<K, V> > {
   }
 };
 
-
-template <typename V>
-class IntKeyRawPointerValueTrait {
- public:
-  typedef intptr_t Key;
-  typedef V Value;
-
-  struct Pair {
-    Key key;
-    Value value;
-    Pair() : key(NULL), value() {}
-    Pair(const Key key, const Value& value) : key(key), value(value) {}
-    Pair(const Pair& other) : key(other.key), value(other.value) {}
-  };
-
-  static Key KeyOf(Pair kv) { return kv.key; }
-  static Value ValueOf(Pair kv) { return kv.value; }
-  static intptr_t Hashcode(Key key) { return reinterpret_cast<intptr_t>(key); }
-  static bool IsKeyEqual(Pair kv, Key key) { return kv.key == key; }
-};
-
-template <typename V>
-class IntMap : public DirectChainedHashMap<IntKeyRawPointerValueTrait<V> > {
- public:
-  typedef typename IntKeyRawPointerValueTrait<V>::Key Key;
-  typedef typename IntKeyRawPointerValueTrait<V>::Value Value;
-  typedef typename IntKeyRawPointerValueTrait<V>::Pair Pair;
-
-  inline void Insert(const Key& key, const Value& value) {
-    Pair pair(key, value);
-    DirectChainedHashMap<IntKeyRawPointerValueTrait<V> >::Insert(pair);
-  }
-
-  inline V Lookup(const Key& key) {
-    Pair* pair =
-        DirectChainedHashMap<IntKeyRawPointerValueTrait<V> >::Lookup(key);
-    if (pair == NULL) {
-      return V();
-    } else {
-      return pair->value;
-    }
-  }
-
-  inline Pair* LookupPair(const Key& key) {
-    return DirectChainedHashMap<IntKeyRawPointerValueTrait<V> >::Lookup(key);
-  }
-};
-
 template <typename K, typename V>
 class MallocMap
     : public MallocDirectChainedHashMap<RawPointerKeyValueTrait<K, V> > {
@@ -550,7 +502,7 @@ class ConstantEvaluator : public ExpressionVisitor {
 
 
 struct FunctionScope {
-  intptr_t kernel_offset;
+  FunctionNode* function;
   LocalScope* scope;
 };
 
@@ -566,8 +518,8 @@ class ScopeBuildingResult : public ZoneAllocated {
         yield_jump_variable(NULL),
         yield_context_variable(NULL) {}
 
-  IntMap<LocalVariable*> locals;
-  IntMap<LocalScope*> scopes;
+  Map<VariableDeclaration, LocalVariable*> locals;
+  Map<TreeNode, LocalScope*> scopes;
   GrowableArray<FunctionScope> function_scopes;
 
   // Only non-NULL for instance functions.