more SkSL IRNode refactoring

Prefix, Postfix, and ExternalFunctionCall nodes this time around.

Change-Id: I56bc06d73274f01b67f043a6ebd23dd4c80d16e8
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/324621
Reviewed-by: John Stiles <johnstiles@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/sksl/SkSLMetalCodeGenerator.cpp b/src/sksl/SkSLMetalCodeGenerator.cpp
index fbeff90..b9375c2 100644
--- a/src/sksl/SkSLMetalCodeGenerator.cpp
+++ b/src/sksl/SkSLMetalCodeGenerator.cpp
@@ -894,8 +894,8 @@
     if (kPrefix_Precedence >= parentPrecedence) {
         this->write("(");
     }
-    this->write(Compiler::OperatorName(p.fOperator));
-    this->writeExpression(*p.fOperand, kPrefix_Precedence);
+    this->write(Compiler::OperatorName(p.getOperator()));
+    this->writeExpression(*p.operand(), kPrefix_Precedence);
     if (kPrefix_Precedence >= parentPrecedence) {
         this->write(")");
     }
@@ -906,8 +906,8 @@
     if (kPostfix_Precedence >= parentPrecedence) {
         this->write("(");
     }
-    this->writeExpression(*p.fOperand, kPostfix_Precedence);
-    this->write(Compiler::OperatorName(p.fOperator));
+    this->writeExpression(*p.operand(), kPostfix_Precedence);
+    this->write(Compiler::OperatorName(p.getOperator()));
     if (kPostfix_Precedence >= parentPrecedence) {
         this->write(")");
     }
@@ -1709,9 +1709,9 @@
             return this->requirements(idx.base().get()) | this->requirements(idx.index().get());
         }
         case Expression::Kind::kPrefix:
-            return this->requirements(e->as<PrefixExpression>().fOperand.get());
+            return this->requirements(e->as<PrefixExpression>().operand().get());
         case Expression::Kind::kPostfix:
-            return this->requirements(e->as<PostfixExpression>().fOperand.get());
+            return this->requirements(e->as<PostfixExpression>().operand().get());
         case Expression::Kind::kTernary: {
             const TernaryExpression& t = e->as<TernaryExpression>();
             return this->requirements(t.test().get()) | this->requirements(t.ifTrue().get()) |