SkTHash: hash from fnptr to functor type

tests/HashTest.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 "SkChecksum.h"
 #include "SkString.h"
 #include "SkTHash.h"
@@ skipping 102 matching lines @@
 
     bool operator==(const CopyCounter& other) const {
         return fID == other.fID;
     }
 
 private:
     uint32_t  fID;
     uint32_t* fCounter;
 };
 
-uint32_t hash_copy_counter(const CopyCounter&) {
-    return 0; // let them collide, what do we care?
-}
+struct HashCopyCounter {
+    uint32_t operator()(const CopyCounter&) const {
+        return 0; // let them collide, what do we care?
+    }
+};
 
 }
 
 DEF_TEST(HashSetCopyCounter, r) {
-    SkTHashSet<CopyCounter, hash_copy_counter> set;
+    SkTHashSet<CopyCounter, HashCopyCounter> set;
 
     uint32_t globalCounter = 0;
     CopyCounter copyCounter1(1, &globalCounter);
     CopyCounter copyCounter2(2, &globalCounter);
     REPORTER_ASSERT(r, globalCounter == 0);
 
     set.add(copyCounter1);
     REPORTER_ASSERT(r, globalCounter == 1);
     REPORTER_ASSERT(r, set.contains(copyCounter1));
     REPORTER_ASSERT(r, globalCounter == 1);
     set.add(copyCounter1);
     // We allow copies for same-value adds for now.
     REPORTER_ASSERT(r, globalCounter == 2);
 
     set.add(copyCounter2);
     REPORTER_ASSERT(r, globalCounter == 3);
     REPORTER_ASSERT(r, set.contains(copyCounter1));
     REPORTER_ASSERT(r, set.contains(copyCounter2));
     REPORTER_ASSERT(r, globalCounter == 3);
     set.add(copyCounter1);
     set.add(copyCounter2);
     // We allow copies for same-value adds for now.
     REPORTER_ASSERT(r, globalCounter == 5);
 }