Add fromIterable(s) constructors in SplayTreeMap and LinkedHashMap.

sdk/lib/collection/hash_map.dart

Index: sdk/lib/collection/hash_map.dart
diff --git a/sdk/lib/collection/hash_map.dart b/sdk/lib/collection/hash_map.dart
index 2d08e35890696589b494681de77adc10dd5cd36c..863276a25a57659c8aa210d14c55ebf9871a5eee 100644
--- a/sdk/lib/collection/hash_map.dart
+++ b/sdk/lib/collection/hash_map.dart
@@ -18,8 +18,6 @@ part of dart.collection;
 class HashMap<K, V> implements Map<K, V> {
   external HashMap();
 
-  static _id(x) => x;
-
   factory HashMap.from(Map<K, V> other) {
     return new HashMap<K, V>()..addAll(other);
   }
@@ -27,36 +25,13 @@ class HashMap<K, V> implements Map<K, V> {
   factory HashMap.fromIterable(Iterable iterable,

[floitsch, 2013/06/27 16:04:32]

Actually I think we need to copy the dart-doc from Map. These classes appear in
the dart-doc separately and don't inherit the doc from there.
Ditto for all other constructors.

[zarah, 2013/06/27 17:00:07]

Done.

       {K key(element), V value(element)}) {
     HashMap<K, V> map = new HashMap<K, V>();
-
-    if (key == null) key = _id;
-    if (value == null) value = _id;
-
-    for (var element in iterable) {
-      map[key(element)] = value(element);
-    }
-
+    Maps._fillMapWithMappedIterable(map, iterable, key: key, value: value);
     return map;
   }
 
   factory HashMap.fromIterables(Iterable<K> keys, Iterable<V> values) {
     HashMap<K, V> map = new HashMap<K, V>();
-
-    Iterator<K> keyIterator = keys.iterator;
-    Iterator<V> valueIterator = values.iterator;
-
-    bool hasNextKey = keyIterator.moveNext();
-    bool hasNextValue = valueIterator.moveNext();
-
-    while (hasNextKey && hasNextValue) {
-      map[keyIterator.current] = valueIterator.current;
-      hasNextKey = keyIterator.moveNext();
-      hasNextValue = valueIterator.moveNext();
-    }
-
-    if (hasNextKey || hasNextValue) {
-      throw new ArgumentError("Iterables do not have same length.");
-    }
-
+    Maps._fillMapWithIterables(map, keys, values);
     return map;
   }