[testing] Remove isCrankshafted

Crankshaft is gone, and this function is not used anywhere.

R=mstarzinger@chromium.org

Bug: v8:7310,v8:6408
Change-Id: Ic1f859e659008c891cc35d20e95a8214de42bd21
Reviewed-on: https://chromium-review.googlesource.com/928981Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51445}

test/mjsunit/mjsunit.js

@@ -169,9 +169,6 @@ var isInterpreted;
 // Returns true if given function is optimized.
 var isOptimized;
 
-// Returns true if given function is compiled by Crankshaft.
-var isCrankshafted;
-
 // Returns true if given function is compiled by TurboFan.
 var isTurboFanned;
 
@@ -670,14 +667,6 @@ var failWithMessage;
     return (opt_status & V8OptimizationStatus.kOptimized) !== 0;
   }
 
-  isCrankshafted = function isCrankshafted(fun) {
-    var opt_status = OptimizationStatus(fun, "");
-    assertTrue((opt_status & V8OptimizationStatus.kIsFunction) !== 0,
-               "not a function");
-    return (opt_status & V8OptimizationStatus.kOptimized) !== 0 &&
-           (opt_status & V8OptimizationStatus.kTurboFanned) === 0;
-  }
-
   isTurboFanned = function isTurboFanned(fun) {
     var opt_status = OptimizationStatus(fun, "");
     assertTrue((opt_status & V8OptimizationStatus.kIsFunction) !== 0,