Add nanobench, a fresh look at our microbenchmark harness.

out/Release/nanobench runs 4-5x faster on my Z620 and ~2x faster on my N5 than out/Release/bench with the same configs.

(Debug isn't really comparable.  I haven't added the Debug -> single loop check.)

BUG=skia:
R=djsollen@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/347443002
diff --git a/gyp/bench.gypi b/gyp/bench.gypi
index 798fdd4..064814a 100644
--- a/gyp/bench.gypi
+++ b/gyp/bench.gypi
@@ -2,11 +2,21 @@
   'include_dirs': [
     '../src/core',
     '../src/effects',
+    '../src/gpu',
     '../src/utils',
     '../tools',
   ],
   'dependencies': [
+    'etc1.gyp:libetc1',
     'skia_lib.gyp:skia_lib',
+    'tools.gyp:resources',
+    'tools.gyp:sk_tool_utils',
+  ],
+  'conditions': [
+    ['skia_gpu == 1', {
+      'include_dirs': [ '../src/gpu' ],
+      'dependencies': [ 'gputest.gyp:skgputest' ],
+    }],
   ],
   'sources': [
     '../bench/Benchmark.cpp',