Remove insertRange.

sdk/lib/collection/list.dart

Index: sdk/lib/collection/list.dart
diff --git a/sdk/lib/collection/list.dart b/sdk/lib/collection/list.dart
index 9128228f71f5e02d3a8bd6e57ddfeee9f08c2f4f..47829d64706f36f56825dff991ae0f78036e0c9a 100644
--- a/sdk/lib/collection/list.dart
+++ b/sdk/lib/collection/list.dart
@@ -324,29 +324,14 @@ abstract class ListMixin<E> implements List<E> {
     return new SubListIterable(this, start, end);
   }
 
-  void insertRange(int start, int length, [E initialValue]) {
+  void removeRange(int start, int end) {
     if (start < 0 || start > this.length) {
       throw new RangeError.range(start, 0, this.length);
     }
-    int oldLength = this.length;
-    int moveLength = oldLength - start;
-    this.length += length;
-    if (moveLength > 0) {
-      this.setRange(start + length, oldLength, this, start);
-    }
-    for (int i = 0; i < length; i++) {
-      this[start + i] = initialValue;
-    }
-  }
-
-  void removeRange(int start, int length) {
-    if (start < 0 || start > this.length) {
-      throw new RangeError.range(start, 0, this.length);
-    }
-    if (length < 0 || start + length > this.length) {
-      throw new RangeError.range(length, 0, this.length - start);
+    if (end < start || end > this.length) {
+      throw new RangeError.range(end, start, this.length);
     }
-    int end = start + length;
+    int length = end - start;
     setRange(start, this.length - length, this, end);
     this.length -= length;
   }