Revert of Remove WebInspector.HeapSnapshotArraySlice

Source/devtools/front_end/HeapSnapshot.js

Index: Source/devtools/front_end/HeapSnapshot.js
diff --git a/Source/devtools/front_end/HeapSnapshot.js b/Source/devtools/front_end/HeapSnapshot.js
index 12b186b808ba0a92f771c70ff81ec941b48b62a4..bd30745c4b9f24182c844736b26bc84eba82ba56 100644
--- a/Source/devtools/front_end/HeapSnapshot.js
+++ b/Source/devtools/front_end/HeapSnapshot.js
@@ -30,8 +30,42 @@
 
 /**
  * @constructor
- * @param {!WebInspector.HeapSnapshot} snapshot
- * @param {!Uint32Array} edges
+ * @param {!Uint32Array} array
+ * @param {number} start
+ * @param {number} end
+ */
+WebInspector.HeapSnapshotArraySlice = function(array, start, end)
+{
+    this._array = array;
+    this._start = start;
+    this.length = end - start;
+}
+
+WebInspector.HeapSnapshotArraySlice.prototype = {
+    /**
+     * @param {number} index
+     * @return {number}
+     */
+    item: function(index)
+    {
+        return this._array[this._start + index];
+    },
+
+    /**
+     * @param {number} start
+     * @param {number=} end
+     * @return {!Uint32Array}
+     */
+    slice: function(start, end)
+    {
+        if (typeof end === "undefined")
+            end = this.length;
+        return this._array.subarray(this._start + start, this._start + end);
+    }
+}
+
+/**
+ * @constructor
  * @param {number=} edgeIndex
  */
 WebInspector.HeapSnapshotEdge = function(snapshot, edges, edgeIndex)
@@ -95,7 +129,15 @@
      */
     nodeIndex: function()
     {
-        return this._edges[this.edgeIndex + this._snapshot._edgeToNodeOffset];
+        return this._edges.item(this.edgeIndex + this._snapshot._edgeToNodeOffset);
+    },
+
+    /**
+     * @return {!Array.<number>}
+     */
+    rawEdges: function()
+    {
+        return this._edges;
     },
 
     /**
@@ -125,7 +167,7 @@
 
     _type: function()
     {
-        return this._edges[this.edgeIndex + this._snapshot._edgeTypeOffset];
+        return this._edges.item(this.edgeIndex + this._snapshot._edgeTypeOffset);
     }
 };
 
@@ -481,11 +523,11 @@
     },
 
     /**
-     * @return {!Uint32Array}
+     * @return {!WebInspector.HeapSnapshotArraySlice}
      */
     rawEdges: function()
     {
-        return this._snapshot._containmentEdges.subarray(this._edgeIndexesStart(), this._edgeIndexesEnd());
+        return new WebInspector.HeapSnapshotArraySlice(this._snapshot._containmentEdges, this._edgeIndexesStart(), this._edgeIndexesEnd());
     },
 
     /**
@@ -956,15 +998,11 @@
         return this._firstDominatedNodeIndex[nodeIndex / this._nodeFieldCount];
     },
 
-    /**
-     * @param {!WebInspector.HeapSnapshotNode} node
-     * @return {!Uint32Array}
-     */
     _dominatedNodesOfNode: function(node)
     {
         var dominatedIndexFrom = this._getDominatedIndex(node.nodeIndex);
         var dominatedIndexTo = this._getDominatedIndex(node._nextNodeIndex());
-        return this._dominatedNodes.subarray(dominatedIndexFrom, dominatedIndexTo);
+        return new WebInspector.HeapSnapshotArraySlice(this._dominatedNodes, dominatedIndexFrom, dominatedIndexTo);
     },
 
     /**
@@ -1892,14 +1930,13 @@
 
 /**
  * @constructor
- * @param {(!Array.<number>|!Uint32Array)=} unfilteredIterationOrder
+ * @param {!Array.<number>=} unfilteredIterationOrder
  */
 WebInspector.HeapSnapshotFilteredOrderedIterator = function(iterator, filter, unfilteredIterationOrder)
 {
     this._filter = filter;
     this._iterator = iterator;
     this._unfilteredIterationOrder = unfilteredIterationOrder;
-    /** @type {?Array.<number>|?Uint32Array} */
     this._iterationOrder = null;
     this._position = 0;
     this._currentComparator = null;
@@ -1913,7 +1950,7 @@
         if (this._iterationOrder)
             return;
         if (this._unfilteredIterationOrder && !this._filter) {
-            this._iterationOrder = this._unfilteredIterationOrder;
+            this._iterationOrder = this._unfilteredIterationOrder.slice(0);
             this._unfilteredIterationOrder = null;
             return;
         }
@@ -1928,7 +1965,8 @@
                     this._iterationOrder.push(iterator.index());
             }
         } else {
-            var order = this._unfilteredIterationOrder;
+            var order = this._unfilteredIterationOrder.constructor === Array ?
+                this._unfilteredIterationOrder : this._unfilteredIterationOrder.slice(0);
             for (var i = 0, l = order.length; i < l; ++i) {
                 iterator.setIndex(order[i]);
                 if (this._filter(iterator.item()))
@@ -1969,7 +2007,8 @@
                 if (this._filter(iterator.item()))
                     return false;
         } else {
-            var order = this._unfilteredIterationOrder;
+            var order = this._unfilteredIterationOrder.constructor === Array ?
+                this._unfilteredIterationOrder : this._unfilteredIterationOrder.slice(0);
             for (var i = 0, l = order.length; i < l; ++i) {
                 iterator.setIndex(order[i]);
                 if (this._filter(iterator.item()))
@@ -2139,7 +2178,7 @@
 /**
  * @constructor
  * @extends {WebInspector.HeapSnapshotFilteredOrderedIterator}
- * @param {(!Array.<number>|!Uint32Array)=} nodeIndexes
+ * @param {!Array.<number>=} nodeIndexes
  */
 WebInspector.HeapSnapshotNodesProvider = function(snapshot, filter, nodeIndexes)
 {