GM: add --writeChecksumBasedFilenames option

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 58 matching lines @@
          * represent identical results.
          */
         bool equals(const GmResultDigest &other) const;
 
         /**
          * Returns a JSON type/value pair representing this result,
          * such as ["bitmap-64bitMD5", 12345].
          */
         Json::Value asJsonTypeValuePair() const;
 
+        /**
+         * Returns the hashtype, such as "bitmap-64bitMD5", as an SkString.
+         */
+        SkString getHashType() const;
+
+        /**
+         * Returns the hash digest value, such as "12345", as an SkString.
+         */
+        SkString getDigestValue() const;
+
     private:
         bool fIsValid; // always check this first--if it's false, other fields are meaningless
         uint64_t fHashDigest;
     };
 
     /**
+     * Encapsulates an SkBitmap and its GmResultDigest, guaranteed to keep them in sync.
+     */
+    class BitmapAndDigest {
+    public:
+        BitmapAndDigest(const SkBitmap &bitmap) : fBitmap(bitmap), fDigest(bitmap) {}
+
+        const SkBitmap fBitmap;
+        const GmResultDigest fDigest;
+    };
+
+    /**
      * Test expectations (allowed image results, etc.)
      */
     class Expectations {
     public:
         /**
          * No expectations at all.
          */
         Expectations(bool ignoreFailure=kDefaultIgnoreFailure);
 
         /**
@@ skipping 143 matching lines @@
          * Returns true if successful.
          */
         static bool Parse(const char *jsonPath, Json::Value *jsonRoot);
 
         Json::Value fJsonRoot;
         Json::Value fJsonExpectedResults;
     };
 
 }
 #endif