use BenchTimer, print in µs

gyp/bench.gyp

 # GYP file to build performance testbench.
 #
 {
   'includes': [
     'apptype_console.gypi',
   ],
   'targets': [
     {
       'target_name': 'bench',
       'type': 'executable',
@@ skipping 34 matching lines @@
       'sources': [
         '../bench/BenchTimer.h',
         '../bench/BenchTimer.cpp',
         '../bench/BenchSysTimer_mach.h',
         '../bench/BenchSysTimer_mach.cpp',
         '../bench/BenchSysTimer_posix.h',
         '../bench/BenchSysTimer_posix.cpp',
         '../bench/BenchSysTimer_windows.h',
         '../bench/BenchSysTimer_windows.cpp',
       ],
-        'include_dirs': [
+      'include_dirs': [
         '../src/core',
         '../src/gpu',
         '../tools',
       ],
+      'direct_dependent_settings': {
+        'include_dirs': ['../bench'],
+      },
       'dependencies': [
         'skia_lib.gyp:skia_lib',
       ],
       'conditions': [
         [ 'skia_os not in ["mac", "ios"]', {
           'sources!': [
             '../bench/BenchSysTimer_mach.h',
             '../bench/BenchSysTimer_mach.cpp',
           ],
         }],
@@ skipping 19 matching lines @@
         ['skia_gpu == 1', {
           'sources': [
             '../bench/BenchGpuTimer_gl.h',
             '../bench/BenchGpuTimer_gl.cpp',
           ],
         }],
       ],
     }
   ],
 }