Fix benchmark build

Summary: Benchmarks were broken by const diff leaving in some code which should not have changed. This was not caught earlier due to benchmarks only being run on travis.

Reviewed By: IanChilds

Differential Revision: D3751151

fbshipit-source-id: 08207ce7ad584d4681a27ec0727bbfdbc1198d05

benchmarks/CSSBenchmark.c

@@ -14,11 +14,11 @@
 
 // Measure functions can be quite slow, for example when measuring text.
 // Simulate this by sleeping for 1 millisecond.
-static CSSSize _measure(const void *context,
-                        const float width,
-                        const CSSMeasureMode widthMode,
-                        const float height,
-                        const CSSMeasureMode heightMode) {
+static CSSSize _measure(void *context,
+                        float width,
+                        CSSMeasureMode widthMode,
+                        float height,
+                        CSSMeasureMode heightMode) {
   const struct timespec sleeptime = {0, 1000000};
   nanosleep(&sleeptime, NULL);
   return (CSSSize){