GM: create GmResultDigest that encapsulates digest type ("bitmap-64bitMD5") and value (12345)

gm/gm_expectations.cpp

Index: gm/gm_expectations.cpp
===================================================================
--- gm/gm_expectations.cpp	(revision 9256)
+++ gm/gm_expectations.cpp	(working copy)
@@ -43,10 +43,10 @@
         return result;
     }
 
-    // TODO(epoger): This currently assumes that the result SkHashDigest was
-    // generated as an SkHashDigest of an SkBitmap.  We'll need to allow for other
+    // TODO(epoger): This currently assumes that the result hash digest is a
+    // uint64_t generated by SkBitmapHasher.  We'll need to allow for other
     // hash types to cover non-bitmaps.
-    Json::Value ActualResultAsJsonValue(const SkHashDigest& result) {
+    Json::Value ActualResultAsJsonValue(uint64_t result) {
         Json::Value jsonValue;
         jsonValue[kJsonKey_ActualResults_AnyStatus_BitmapHash] = asJsonValue(result);
         return jsonValue;
@@ -78,7 +78,7 @@
     Expectations::Expectations(const SkBitmap& bitmap, bool ignoreFailure) {
         fBitmap = bitmap;
         fIgnoreFailure = ignoreFailure;
-        SkHashDigest digest;
+        uint64_t digest;
         // TODO(epoger): Better handling for error returned by ComputeDigest()?
         // For now, we just report a digest of 0 in error cases, like before.
         if (!SkBitmapHasher::ComputeDigest(bitmap, &digest)) {