Beings adding SIMD support to arm64.

runtime/vm/flow_graph_compiler_arm64.cc

Index: runtime/vm/flow_graph_compiler_arm64.cc
===================================================================
--- runtime/vm/flow_graph_compiler_arm64.cc	(revision 36461)
+++ runtime/vm/flow_graph_compiler_arm64.cc	(working copy)
@@ -26,7 +26,9 @@
 DECLARE_FLAG(int, optimization_counter_threshold);
 DECLARE_FLAG(int, reoptimization_counter_threshold);
 DECLARE_FLAG(bool, eliminate_type_checks);
+DECLARE_FLAG(bool, enable_simd_inline);
 
+
 FlowGraphCompiler::~FlowGraphCompiler() {
   // BlockInfos are zone-allocated, so their destructors are not called.
   // Verify the labels explicitly here.
@@ -47,7 +49,7 @@
 
 
 bool FlowGraphCompiler::SupportsUnboxedSimd128() {
-  return false;
+  return FLAG_enable_simd_inline;
 }