Remove leftover declaration in isolate.h

R=yangguo@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2150483002
Cr-Commit-Position: refs/heads/master@{#37706}

src/isolate.h

@@ -701,8 +701,6 @@ class Isolate {
   MaybeHandle<JSReceiver> CaptureAndSetSimpleStackTrace(
       Handle<JSReceiver> error_object, Handle<Object> caller);
   Handle<JSArray> GetDetailedStackTrace(Handle<JSObject> error_object);
-  Handle<JSArray> GetDetailedFromSimpleStackTrace(
-      Handle<JSObject> error_object);
 
   // Returns if the given context may access the given global object. If
   // the result is false, the pending exception is guaranteed to be