Remove unused

Author: kevintang2022

presto-spi/src/main/java/com/facebook/presto/spi/function/SqlFunction.java

@@ -13,8 +13,6 @@
  */
 package com.facebook.presto.spi.function;
 
-import java.util.Optional;
-
 import static com.facebook.presto.spi.function.ComplexTypeFunctionDescriptor.defaultFunctionDescriptor;
 
 public interface SqlFunction
@@ -27,11 +25,6 @@ public interface SqlFunction
 
     boolean isCalledOnNullInput();
 
-    default Optional<Integer> getPushdownSubfieldArgIndex()
-    {
-        return Optional.empty();
-    }
-
     String getDescription();
 
     default ComplexTypeFunctionDescriptor getComplexTypeFunctionDescriptor()

presto-spi/src/main/java/com/facebook/presto/spi/function/SqlInvokedScalarFunction.java

@@ -31,6 +31,4 @@
     boolean deterministic();
 
     boolean calledOnNullInput();
-
-    int pushdownSubfieldArgIndex() default -1;
 }