Fixes bug where we would occasionally materialize a corrupted object.

runtime/vm/intermediate_language.h

Index: runtime/vm/intermediate_language.h
diff --git a/runtime/vm/intermediate_language.h b/runtime/vm/intermediate_language.h
index db420de6ee90323ae94feaeac6c22d41b222d650..9c2e5da2af9a5b70f8f08db6f4e09e1bb1b51b42 100644
--- a/runtime/vm/intermediate_language.h
+++ b/runtime/vm/intermediate_language.h
@@ -4200,6 +4200,9 @@ class MaterializeObjectInstr : public Definition {
 
   virtual bool MayThrow() const { return false; }
 
+  void RemapRegisters(intptr_t* fpu_reg_slots,
+                      intptr_t* cpu_reg_slots);
+
  private:
   virtual void RawSetInputAt(intptr_t i, Value* value) {
     (*values_)[i] = value;
@@ -7720,6 +7723,7 @@ class Environment : public ZoneAllocated {
   void DeepCopyToOuter(Instruction* instr) const;
 
   void PrintTo(BufferFormatter* f) const;
+  const char* ToCString() const;
 
  private:
   friend class ShallowIterator;