DM: duh, don't calculate digests unless we're going to look at them.

dm/DMUtil.cpp

Index: dm/DMUtil.cpp
diff --git a/dm/DMUtil.cpp b/dm/DMUtil.cpp
index 803c338adce932fd3f1244a9af4609bff75ca92e..dc652ebdbed55176db5c5d6f7aa066db3e138918 100644
--- a/dm/DMUtil.cpp
+++ b/dm/DMUtil.cpp
@@ -13,11 +13,12 @@ SkString png(SkString s) {
     return s;
 }
 
-bool meetsExpectations(const skiagm::Expectations& expectations,
-                       const skiagm::GmResultDigest& digest) {
-    return expectations.ignoreFailure()
-        || expectations.empty()
-        || expectations.match(digest);
+bool meetsExpectations(const skiagm::Expectations& expectations, const SkBitmap bitmap) {
+    if (expectations.ignoreFailure() || expectations.empty()) {
+        return true;
+    }
+    const skiagm::GmResultDigest digest(bitmap);
+    return expectations.match(digest);
 }
 
 }  // namespace DM