Rename FlowGraphOptimizer -> JitOptimizer, clean up optimizer code.

runtime/vm/aot_optimizer.h

Index: runtime/vm/aot_optimizer.h
diff --git a/runtime/vm/aot_optimizer.h b/runtime/vm/aot_optimizer.h
index e770ffea1d1a9ca1873bbe54ce1541e80445021c..3d1ed1bded001ad9d4ca5dd74286423f8649ded9 100644
--- a/runtime/vm/aot_optimizer.h
+++ b/runtime/vm/aot_optimizer.h
@@ -74,11 +74,9 @@ class AotOptimizer : public FlowGraphVisitor {
   bool TryReplaceWithEqualityOp(InstanceCallInstr* call, Token::Kind op_kind);
   bool TryReplaceWithRelationalOp(InstanceCallInstr* call, Token::Kind op_kind);
 
-  bool TryInlineInstanceGetter(InstanceCallInstr* call,
-                               bool allow_check = true);
+  bool TryInlineInstanceGetter(InstanceCallInstr* call);
   bool TryInlineInstanceSetter(InstanceCallInstr* call,
-                               const ICData& unary_ic_data,
-                               bool allow_check = true);
+                               const ICData& unary_ic_data);
 
   bool TryInlineInstanceMethod(InstanceCallInstr* call);
   bool TryInlineFloat32x4Constructor(StaticCallInstr* call,
@@ -142,7 +140,7 @@ class AotOptimizer : public FlowGraphVisitor {
                               Token::Kind op_kind);
   bool InlineFloat64x2BinaryOp(InstanceCallInstr* call,
                                Token::Kind op_kind);
-  bool InlineImplicitInstanceGetter(InstanceCallInstr* call, bool allow_check);
+  bool InlineImplicitInstanceGetter(InstanceCallInstr* call);
 
   RawBool* InstanceOfAsBool(const ICData& ic_data,
                             const AbstractType& type,