Initial isolate reload support

runtime/vm/class_table.h

Index: runtime/vm/class_table.h
diff --git a/runtime/vm/class_table.h b/runtime/vm/class_table.h
index 97e475a689410095261142ea075319c0a65061d4..af774a003718414e967458fbc599db0830e7a47d 100644
--- a/runtime/vm/class_table.h
+++ b/runtime/vm/class_table.h
@@ -156,6 +156,10 @@ class ClassTable {
     return table_[index];
   }
 
+  void SetAt(intptr_t index, RawClass* raw_cls) {
+    table_[index] = raw_cls;
+  }
+
   bool IsValidIndex(intptr_t index) const {
     return (index > 0) && (index < top_);
   }
@@ -167,6 +171,12 @@ class ClassTable {
 
   intptr_t NumCids() const { return top_; }
 
+  // Used to drop recently added classes.
+  void SetNumCids(intptr_t num_cids) {
+    ASSERT(num_cids <= top_);
+    top_ = num_cids;
+  }
+
   void Register(const Class& cls);
 
   void RegisterAt(intptr_t index, const Class& cls);