Split deopt-after and deopt-before handling:

runtime/vm/flow_graph_compiler_x64.cc

Index: runtime/vm/flow_graph_compiler_x64.cc
===================================================================
--- runtime/vm/flow_graph_compiler_x64.cc	(revision 11719)
+++ runtime/vm/flow_graph_compiler_x64.cc	(working copy)
@@ -24,16 +24,16 @@
 DECLARE_FLAG(bool, trace_functions);
 
 
-void DeoptimizationStub::GenerateCode(FlowGraphCompiler* compiler,
-                                      intptr_t stub_ix) {
+void CompilerDeoptInfoWithStub::GenerateCode(FlowGraphCompiler* compiler,
+                                             intptr_t stub_ix) {
   // Calls do not need stubs, they share a deoptimization trampoline.
-  if (reason_ == kDeoptAtCall) return;
+  ASSERT(reason() != kDeoptAtCall);
   Assembler* assem = compiler->assembler();
 #define __ assem->
-  __ Comment("Deopt stub for id %d", deopt_id_);
+  __ Comment("Deopt stub for id %d", deopt_id());
   __ Bind(entry_label());
 
-  ASSERT(deoptimization_env_ != NULL);
+  ASSERT(deoptimization_env() != NULL);
 
   if (compiler->IsLeaf()) {
     __ Comment("Leaf method, lazy PC marker setup");
@@ -54,8 +54,8 @@
   const intptr_t deopt_info_index = stub_ix;
   compiler->pc_descriptors_list()->AddDeoptIndex(
       compiler->assembler()->CodeSize(),
-      deopt_id_,
-      reason_,
+      deopt_id(),
+      reason(),
       deopt_info_index);
   __ int3();
 #undef __