AOT: Add a separate switchable call state for unlinked calls.

runtime/vm/raw_object.h

Index: runtime/vm/raw_object.h
diff --git a/runtime/vm/raw_object.h b/runtime/vm/raw_object.h
index 9e40136f949b022e97f22d25dea09af38dec0b40..66b2d4c4702f1d8f1a7953d839723f6c5947f73c 100644
--- a/runtime/vm/raw_object.h
+++ b/runtime/vm/raw_object.h
@@ -40,6 +40,7 @@ namespace dart {
   V(Context)                                                                   \
   V(ContextScope)                                                              \
   V(SingleTargetCache)                                                         \
+  V(UnlinkedCall)                                                              \
   V(ICData)                                                                    \
   V(MegamorphicCache)                                                          \
   V(SubtypeTestCache)                                                          \
@@ -1509,6 +1510,19 @@ class RawSingleTargetCache : public RawObject {
 };
 
 
+class RawUnlinkedCall : public RawObject {
+  RAW_HEAP_OBJECT_IMPLEMENTATION(UnlinkedCall);
+  RawObject** from() {
+    return reinterpret_cast<RawObject**>(&ptr()->target_name_);
+  }
+  RawString* target_name_;
+  RawArray* args_descriptor_;
+  RawObject** to() {
+    return reinterpret_cast<RawObject**>(&ptr()->args_descriptor_);
+  }
+};
+
+
 class RawICData : public RawObject {
   RAW_HEAP_OBJECT_IMPLEMENTATION(ICData);