Reduce PassDriver overhead, clean up Pass and PassDriver.

Remove name lookup map and use vector for the pass list.
Add traversal mode kNoNodes to skip BasicBlock traversal.
Replace the warn_override parameter with a DCHECK.
Move iterators from arena to the stack. Style cleanup.

Change-Id: I4bf10e28caa65efb98ce82a4d7486d803ceca535
diff --git a/compiler/dex/dataflow_iterator-inl.h b/compiler/dex/dataflow_iterator-inl.h
index 0ca1a47..f8b9c1a 100644
--- a/compiler/dex/dataflow_iterator-inl.h
+++ b/compiler/dex/dataflow_iterator-inl.h
@@ -107,7 +107,7 @@
   // Find the next BasicBlock.
   while (keep_looking == true) {
     // Get next BasicBlock.
-    res = all_nodes_iterator_->Next();
+    res = all_nodes_iterator_.Next();
 
     // Are we done or is the BasicBlock not hidden?
     if ((res == NULL) || (res->hidden == false)) {