"dead" and "osr" block flags added to trace output.

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index ac911d362a3bc9432a40e9e0235d3df75f11ae5f..90f9c3496b2b4c6853419d218ae96fab4c637820 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -10717,10 +10717,21 @@ void HTracer::Trace(const char* name, HGraph* graph, LChunk* chunk) {
     }
 
     PrintEmptyProperty("xhandlers");
-    const char* flags = current->IsLoopSuccessorDominator()
-        ? "dom-loop-succ"
-        : "";
-    PrintStringProperty("flags", flags);
+
+    {
+      PrintIndent();
+      trace_.Add("flags");
+      if (current->IsLoopSuccessorDominator()) {
+        trace_.Add(" \"dom-loop-succ\"");
+      }
+      if (current->IsUnreachable()) {
+        trace_.Add(" \"dead\"");
+      }
+      if (current->is_osr_entry()) {
+        trace_.Add(" \"osr\"");
+      }
+      trace_.Add("\n");
+    }
 
     if (current->dominator() != NULL) {
       PrintBlockProperty("dominator", current->dominator()->block_id());