Switch cc to std::unordered_*.

cc/raster/task_graph_work_queue.cc

Index: cc/raster/task_graph_work_queue.cc
diff --git a/cc/raster/task_graph_work_queue.cc b/cc/raster/task_graph_work_queue.cc
index 87800576dd5177b9e4f2bba196a550c6b8e27c7e..29474023c6539a17ab44c9cc8b0b0d67645dd635 100644
--- a/cc/raster/task_graph_work_queue.cc
+++ b/cc/raster/task_graph_work_queue.cc
@@ -9,6 +9,7 @@
 
 #include <algorithm>
 #include <map>
+#include <unordered_map>
 #include <utility>
 
 #include "base/trace_event/trace_event.h"
@@ -283,7 +284,7 @@ void TaskGraphWorkQueue::CollectCompletedTasks(NamespaceToken token,
 
 bool TaskGraphWorkQueue::DependencyMismatch(const TaskGraph* graph) {
   // Value storage will be 0-initialized.
-  base::hash_map<const Task*, size_t> dependents;
+  std::unordered_map<const Task*, size_t> dependents;
   for (const TaskGraph::Edge& edge : graph->edges)
     dependents[edge.dependent]++;