Change assert implementation to not depend on a top-level function called 'assert'.

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 29b28fdb5ec358b9599466cb610f5bda07c947d7..2c4f46eb9fca804504057c3146675d9bb431b4f3 100644
--- a/runtime/vm/intermediate_language.h
+++ b/runtime/vm/intermediate_language.h
@@ -777,7 +777,6 @@ class GraphEntryInstr : public BlockEntryInstr {
   void set_start_env(Environment* env) { start_env_ = env; }
 
   ConstantInstr* constant_null() const { return constant_null_; }
-  void set_constant_null(ConstantInstr* instr) { constant_null_ = instr; }
 
   intptr_t spill_slot_count() const { return spill_slot_count_; }
   void set_spill_slot_count(intptr_t count) {
@@ -1155,7 +1154,7 @@ class ParameterInstr : public Definition {
     return kIllegalCid;
   }
 
-  virtual void PrintOperandsTo(BufferFormatter* f) const;
+  virtual void PrintTo(BufferFormatter* f) const;
   virtual void PrintToVisualizer(BufferFormatter* f) const;
 
  private:
@@ -1210,7 +1209,7 @@ class PushArgumentInstr : public Definition {
 
   virtual bool CanDeoptimize() const { return false; }
 
-  virtual void PrintOperandsTo(BufferFormatter* f) const;
+  virtual void PrintTo(BufferFormatter* f) const;
   virtual void PrintToVisualizer(BufferFormatter* f) const;
 
  private:
@@ -1746,7 +1745,7 @@ class PolymorphicInstanceCallInstr : public TemplateDefinition<0> {
   virtual bool CanDeoptimize() const { return true; }
   virtual intptr_t ResultCid() const { return kDynamicCid; }
 
-  virtual void PrintOperandsTo(BufferFormatter* f) const;
+  virtual void PrintTo(BufferFormatter* f) const;
 
  private:
   InstanceCallInstr* instance_call_;