Adding deopt info to code object.

runtime/vm/code_descriptors.h

Index: runtime/vm/code_descriptors.h
===================================================================
--- runtime/vm/code_descriptors.h	(revision 10182)
+++ runtime/vm/code_descriptors.h	(working copy)
@@ -18,7 +18,7 @@
     PcDescriptors::Kind kind;  // Descriptor kind (kDeopt, kOther).
     intptr_t node_id;          // AST node id.
     intptr_t token_index;      // Token position in source of PC.
-    intptr_t try_index;        // Try block index of PC.
+    intptr_t try_index;        // Try block index of PC or deopt array index.
   };
 
   explicit DescriptorList(intptr_t initial_capacity) : list_(initial_capacity) {
@@ -50,6 +50,10 @@
                      intptr_t node_id,
                      intptr_t token_index,
                      intptr_t try_index);
+  void AddDeoptInfo(intptr_t pc_offset,
+                    intptr_t node_id,
+                    intptr_t token_index,
+                    intptr_t deopt_array_index);
 
   RawPcDescriptors* FinalizePcDescriptors(uword entry_point);