Fix for nexus 5 crashing in GL benches

bench/nanobench.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include <ctype.h>
 
 #include "nanobench.h"
@@ skipping 190 matching lines @@
     }
 };
 
 #endif
 
 static double time(int loops, Benchmark* bench, Target* target) {
     SkCanvas* canvas = target->getCanvas();
     if (canvas) {
         canvas->clear(SK_ColorWHITE);
     }
+    bench->perCanvasLastCallBeforeDraw(canvas);
     WallTimer timer;
     timer.start();
     canvas = target->beginTiming(canvas);
     bench->draw(loops, canvas);
     if (canvas) {
         canvas->flush();
     }
     target->endTiming();
     timer.end();
+    bench->perCanvasFirstCallAfterDraw(canvas);
     return timer.fWall;
 }
 
 static double estimate_timer_overhead() {
     double overhead = 0;
     for (int i = 0; i < FLAGS_overheadLoops; i++) {
         WallTimer timer;
         timer.start();
         timer.end();
         overhead += timer.fWall;
@@ skipping 1063 matching lines @@
 
     return 0;
 }
 
 #if !defined SK_BUILD_FOR_IOS
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return nanobench_main();
 }
 #endif