Add mssa configs for vulkan, and simple bug fix

tools/flags/SkCommonFlagsConfig.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 "SkCommonFlagsConfig.h"
 
 #include <stdlib.h>
@@ skipping 109 matching lines @@
 #endif
 #if SK_COMMAND_BUFFER
     "\tcommandbuffer\t= gpu(api=commandbuffer)\n"
 #endif
 #if SK_MESA
     "\tmesa      \t= gpu(api=mesa)\n"
 #endif
 #ifdef SK_VULKAN
     "\tvk        \t= gpu(api=vulkan)\n"
     "\tvksrgb    \t= gpu(api=vulkan,color=srgb)\n"
+    "\tvkmsaa4   \t= gpu(api=gl,samples=4)\n"
+    "\tvkmsaa16  \t= gpu(api=gl,samples=16)\n"
 #endif
 #endif
     ;
 
 DEFINE_extended_string(config, defaultConfigs, configHelp, configExtendedHelp);
 
 static const struct {
     const char* predefinedConfig;
     const char* backend;
     const char* options;
@@ skipping 32 matching lines @@
 #endif
     , { "angle-gl",   "gpu", "api=angle-gl" }
 #endif
 #if SK_COMMAND_BUFFER
     , { "commandbuffer", "gpu", "api=commandbuffer" }
 #endif
 #if SK_MESA
     , { "mesa", "gpu", "api=mesa" }
 #endif
 #ifdef SK_VULKAN
-    , { "vk", "gpu", "api=vulkan" }
-    , { "vksrgb", "gpu", "api=vulkan,color=srgb" }
+    , { "vk",       "gpu", "api=vulkan" }
+    , { "vksrgb",   "gpu", "api=vulkan,color=srgb" }
+    , { "vkmsaa4",  "gpu", "api=vulkan,samples=4" }
+    , { "vkmsaa16", "gpu", "api=vulkan,samples=16" }
 #endif
 
 #else
     { "", "", "" }
 #endif
 };
 
 SkCommandLineConfig::SkCommandLineConfig(const SkString& tag, const SkString& backend,
                                          const SkTArray<SkString>& viaParts)
         : fTag(tag)
@@ skipping 223 matching lines @@
         if (extendedBackend.equals("gpu")) {
             parsedConfig = parse_command_line_config_gpu(tag, vias, extendedOptions);
         }
 #endif
         if (!parsedConfig) {
             parsedConfig = new SkCommandLineConfig(tag, simpleBackend, vias);
         }
         outResult->emplace_back(parsedConfig);
     }
 }