GM: make behavior of make_filename() more late-binding

gm/gm_expectations.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef gm_expectations_DEFINED
 #define gm_expectations_DEFINED
 
 #include "gm.h"
@@ skipping 33 matching lines @@
     /**
      * Assembles rootPath and relativePath into a single path, like this:
      * rootPath/relativePath
      *
      * Uses SkPATH_SEPARATOR, to work on all platforms.
      *
      * TODO(epoger): This should probably move into SkOSFile.h
      */
     SkString SkPathJoin(const char *rootPath, const char *relativePath);
 
-    SkString make_filename(const char path[],
-                           const char renderModeDescriptor[],
-                           const char *name,
-                           const char suffix[]);
-
     Json::Value ActualResultAsJsonValue(const SkHashDigest& result);
 
     Json::Value CreateJsonTree(Json::Value expectedResults,
                                Json::Value actualResultsFailed,
                                Json::Value actualResultsFailureIgnored,
                                Json::Value actualResultsNoComparison,
                                Json::Value actualResultsSucceeded);
 
     /**
      * Test expectations (allowed image checksums, etc.)
@@ skipping 152 matching lines @@
          * Returns true if successful.
          */
         static bool Parse(const char *jsonPath, Json::Value *jsonRoot);
 
         Json::Value fJsonRoot;
         Json::Value fJsonExpectedResults;
     };
 
 }
 #endif