VM: Link native calls lazily.

runtime/vm/instructions_arm64.h

Index: runtime/vm/instructions_arm64.h
diff --git a/runtime/vm/instructions_arm64.h b/runtime/vm/instructions_arm64.h
index 568d57e8ac00e9f0bc24de4c3f2f70107112f868..c923ed608573e1a5f0c379dad34e9f6e0fde67e1 100644
--- a/runtime/vm/instructions_arm64.h
+++ b/runtime/vm/instructions_arm64.h
@@ -11,6 +11,7 @@
 #endif
 
 #include "vm/constants_arm64.h"
+#include "vm/native_entry.h"
 #include "vm/object.h"
 
 namespace dart {
@@ -85,6 +86,27 @@ class CallPattern : public ValueObject {
 };
 
 
+class NativeCallPattern : public ValueObject {
+ public:
+  NativeCallPattern(uword pc, const Code& code);
+
+  uword target() const;
+  void set_target(uword target_address) const;
+
+  NativeFunction native_function() const;
+  void set_native_function(NativeFunction target) const;
+
+ private:
+  const ObjectPool& object_pool_;
+
+  uword end_;
+  intptr_t native_function_pool_index_;
+  intptr_t target_address_pool_index_;
+
+  DISALLOW_COPY_AND_ASSIGN(NativeCallPattern);
+};
+
+
 class JumpPattern : public ValueObject {
  public:
   JumpPattern(uword pc, const Code& code);