Fix analyzer hints in pkg/collection.

pkg/collection/lib/src/unmodifiable_wrappers.dart

Index: pkg/collection/lib/src/unmodifiable_wrappers.dart
diff --git a/pkg/collection/lib/src/unmodifiable_wrappers.dart b/pkg/collection/lib/src/unmodifiable_wrappers.dart
index 022bbfe17427fb68e25e2cc57f7c0302df30c5ce..a60ca3dd5b2a4b675598467dab80a71099aa098a 100644
--- a/pkg/collection/lib/src/unmodifiable_wrappers.dart
+++ b/pkg/collection/lib/src/unmodifiable_wrappers.dart
@@ -53,6 +53,7 @@ abstract class NonGrowableListMixin<E> implements List<E> {
    */
   bool add(E value) {
     _throw();
+    throw 'unreachable';

[Lasse Reichstein Nielsen, 2014/05/29 21:55:06]

Maybe change _throw to return dynamic and write this as:
  return _throw();
where the return type isn't void.

I think I prefer that to an unreachable line that looks like it throws a string.

[nweiz, 2014/05/30 00:49:41]

Done.

   }
 
   /**
@@ -77,19 +78,28 @@ abstract class NonGrowableListMixin<E> implements List<E> {
    * Throws an [UnsupportedError];
    * operations that change the length of the list are disallowed.
    */
-  bool remove(Object value) { _throw(); }
+  bool remove(Object value) {
+    _throw();
+    throw 'unreachable';
+  }
 
   /**
    * Throws an [UnsupportedError];
    * operations that change the length of the list are disallowed.
    */
-  E removeAt(int index) { _throw(); }
+  E removeAt(int index) {
+    _throw();
+    throw 'unreachable';
+  }
 
   /**
    * Throws an [UnsupportedError];
    * operations that change the length of the list are disallowed.
    */
-  E removeLast() { _throw(); }
+  E removeLast() {
+    _throw();
+    throw 'unreachable';
+  }
 
   /**
    * Throws an [UnsupportedError];
@@ -151,6 +161,7 @@ abstract class UnmodifiableSetMixin<E> implements Set<E> {
    */
   bool add(E value) {
     _throw();
+    throw 'unreachable';
   }
 
   /**
@@ -163,7 +174,10 @@ abstract class UnmodifiableSetMixin<E> implements Set<E> {
    * Throws an [UnsupportedError];
    * operations that change the set are disallowed.
    */
-  bool remove(Object value) { _throw(); }
+  bool remove(Object value) {
+    _throw();
+    throw 'unreachable';
+  }
 
   /**
    * Throws an [UnsupportedError];
@@ -229,7 +243,10 @@ abstract class UnmodifiableMapMixin<K, V> implements Map<K, V> {
    * Throws an [UnsupportedError];
    * operations that change the map are disallowed.
    */
-  V putIfAbsent(K key, V ifAbsent()) { _throw(); }
+  V putIfAbsent(K key, V ifAbsent()) {
+    _throw();
+    throw 'unreachable';
+  }
 
   /**
    * Throws an [UnsupportedError];
@@ -241,7 +258,10 @@ abstract class UnmodifiableMapMixin<K, V> implements Map<K, V> {
    * Throws an [UnsupportedError];
    * operations that change the map are disallowed.
    */
-  V remove(K key) { _throw(); }
+  V remove(K key) {
+    _throw();
+    throw 'unreachable';
+  }
 
   /**
    * Throws an [UnsupportedError];