Fix crash in OSR with --optimization-counter-threshold=-1: do not check for OSR if the optimizaiton…

runtime/vm/flow_graph_compiler.cc

Index: runtime/vm/flow_graph_compiler.cc
===================================================================
--- runtime/vm/flow_graph_compiler.cc	(revision 24103)
+++ runtime/vm/flow_graph_compiler.cc	(working copy)
@@ -30,6 +30,7 @@
 DECLARE_FLAG(bool, report_usage_count);
 DECLARE_FLAG(int, optimization_counter_threshold);
 DECLARE_FLAG(bool, use_cha);
+DECLARE_FLAG(bool, use_osr);
 
 
 // Assign locations to incoming arguments, i.e., values pushed above spill slots
@@ -164,6 +165,11 @@
 }
 
 
+bool FlowGraphCompiler::CanOSRFunction() const {
+  return FLAG_use_osr & CanOptimizeFunction() && !is_optimizing();
+}
+
+
 static bool IsEmptyBlock(BlockEntryInstr* block) {
   return !block->HasParallelMove() &&
          block->next()->IsGoto() &&