Reapply "Initial implementation of sparse conditional constant propagation."

runtime/vm/object.h

Index: runtime/vm/object.h
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index abb84c5e43e70099473923cd834a8ebca94b6d6b..d92c3fe83673f62fcb616a64fb490d3606bbc95b 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -3248,6 +3248,11 @@ class Integer : public Number {
   // Returns 0, -1 or 1.
   virtual int CompareWith(const Integer& other) const;
 
+  static RawInteger* AsInteger(const Integer& value);
+  static RawInteger* BinaryOp(Token::Kind operation,
+                              const Integer& left,
+                              const Integer& right);
+
   OBJECT_IMPLEMENTATION(Integer, Number);
   friend class Class;
 };
@@ -3389,6 +3394,11 @@ class Bigint : public Integer {
   static RawBigint* New(const String& str, Heap::Space space = Heap::kNew);
   static RawBigint* New(int64_t value, Heap::Space space = Heap::kNew);
 
+  static RawBigint* AsBigint(const Integer& value);
+  static RawBigint* BinaryOp(Token::Kind operation,
+                             const Bigint& left,
+                             const Bigint& right);
+
  private:
   Chunk GetChunkAt(intptr_t i) const {
     return *ChunkAddr(i);