[turbofan] Use builtin inlining mechanism for Math.abs and Math.sqrt.

src/compiler/js-builtin-reducer.h

Index: src/compiler/js-builtin-reducer.h
diff --git a/src/compiler/js-builtin-reducer.h b/src/compiler/js-builtin-reducer.h
index 60b9e1438a148dbcff8ba5f39f0f6fdf8ea8703d..42221e972715737467ff9f6ac72d6569d8684495 100644
--- a/src/compiler/js-builtin-reducer.h
+++ b/src/compiler/js-builtin-reducer.h
@@ -26,8 +26,6 @@ class JSBuiltinReducer FINAL : public Reducer {
   Reduction Reduce(Node* node) FINAL;
 
  private:
-  Reduction ReduceMathAbs(Node* node);
-  Reduction ReduceMathSqrt(Node* node);
   Reduction ReduceMathMax(Node* node);
   Reduction ReduceMathImul(Node* node);
   Reduction ReduceMathFround(Node* node);