vb: also thread --key through to .json

tools/VisualBench/VisualLightweightBenchModule.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  */
 
 #include "VisualLightweightBenchModule.h"
 
@@ skipping 13 matching lines @@
 __SK_FORCE_IMAGE_DECODER_LINKING;
 
 // Between samples we reset context
 // Between frames we swap buffers
 
 DEFINE_int32(gpuFrameLag, 5, "Overestimate of maximum number of frames GPU allows to lag.");
 DEFINE_int32(samples, 10, "Number of times to time each skp.");
 DEFINE_int32(frames, 5, "Number of frames of each skp to render per sample.");
 DEFINE_double(loopMs, 5, "Target loop time in millseconds.");
 DEFINE_bool2(verbose, v, false, "enable verbose output from the test driver.");
-DEFINE_string(key, "", "");  // dummy to enable gm tests that have platform-specific names
 DEFINE_string(outResultsFile, "", "If given, write results here as JSON.");
+DEFINE_string(key, "",
+              "Space-separated key/value pairs to add to JSON identifying this builder.");
 DEFINE_string(properties, "",
               "Space-separated key/value pairs to add to JSON identifying this run.");
 
 static SkString humanize(double ms) {
     if (FLAGS_verbose) {
         return SkStringPrintf("%llu", (uint64_t)(ms*1e6));
     }
     return HumanizeMs(ms);
 }
 
@@ skipping 10 matching lines @@
     fBenchmarkStream.reset(new VisualBenchmarkStream);
 
     // Print header
     SkDebugf("curr/maxrss\tloops\tflushes\tmin\tmedian\tmean\tmax\tstddev\tbench\n");
 
     // setup json logging if required
     if (!FLAGS_outResultsFile.isEmpty()) {
         fResults.reset(new NanoJSONResultsWriter(FLAGS_outResultsFile[0]));
     }
 
+    if (1 == FLAGS_key.count() % 2) {
+        SkDebugf("ERROR: --key must be passed with an even number of arguments.\n");
+    } else {
+        for (int i = 1; i < FLAGS_key.count(); i += 2) {
+            fResults->key(FLAGS_key[i - 1], FLAGS_key[i]);
+        }
+    }
+
     if (1 == FLAGS_properties.count() % 2) {
         SkDebugf("ERROR: --properties must be passed with an even number of arguments.\n");
     } else {
         for (int i = 1; i < FLAGS_properties.count(); i += 2) {
             fResults->property(FLAGS_properties[i - 1], FLAGS_properties[i]);
         }
     }
 }
 
 inline void VisualLightweightBenchModule::renderFrame(SkCanvas* canvas) {
@@ skipping 177 matching lines @@
         }
         this->resetTimingState();
     } else {
         fCurrentFrame++;
     }
 }
 
 bool VisualLightweightBenchModule::onHandleChar(SkUnichar c) {
     return true;
 }