Wire up configurations properly in VisualBench

tools/VisualBench/VisualFlags.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef VisualFlags_DEFINED
 #define VisualFlags_DEFINED
 
 #include "SkCommandLineFlags.h"
 
+struct Configs {
+    struct Config {
+       enum Type {
+           kGpu_Type,
+           kMsaa_Type,
+           kNvpr_Type,
+           kCpu_Type,
+       };
+       Type fType;
+       int fNumSamples;
+
+       SkString humanReadable() const;
+    };
+    SkTArray<Config> fList;
+    int fIter;
+
+    Configs() { fIter = 0; }
+    Config& push_back() { return fList.push_back(); }
+    const Config& current() const { return fList[fIter]; }
+    bool next() { fIter++; return fIter >= fList.count(); }
+};
+
 DECLARE_string(config);
-DECLARE_int32(msaa);
-DECLARE_bool(nvpr);
 
 #endif