[turbofan] Move lowering of Float64 optional operators to EffectControlLinearizer.

src/compiler/effect-control-linearizer.h

Index: src/compiler/effect-control-linearizer.h
diff --git a/src/compiler/effect-control-linearizer.h b/src/compiler/effect-control-linearizer.h
index 1a4957746ea091cabd1df19337a2609fd2804f63..c92753345e90b87218edf924a912681ffaf240cf 100644
--- a/src/compiler/effect-control-linearizer.h
+++ b/src/compiler/effect-control-linearizer.h
@@ -143,6 +143,14 @@ class EffectControlLinearizer {
   ValueEffectControl LowerStoreTypedElement(Node* node, Node* effect,
                                             Node* control);
 
+  // Lowering of optional operators.
+  ValueEffectControl LowerFloat64RoundUp(Node* node, Node* effect,
+                                         Node* control);
+  ValueEffectControl LowerFloat64RoundDown(Node* node, Node* effect,
+                                           Node* control);
+  ValueEffectControl LowerFloat64RoundTruncate(Node* node, Node* effect,
+                                               Node* control);
+
   ValueEffectControl AllocateHeapNumberWithValue(Node* node, Node* effect,
                                                  Node* control);
   ValueEffectControl BuildCheckedFloat64ToInt32(CheckForMinusZeroMode mode,