Pepper: Log in UMA when an interface is used.

ppapi/tools/pepper_hash_for_uma.cc

Index: ppapi/tools/pepper_hash_for_uma.cc
diff --git a/ppapi/tools/pepper_hash_for_uma.cc b/ppapi/tools/pepper_hash_for_uma.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f7c5e236609f01b233a038abcc94a73a2d2aa969
--- /dev/null
+++ b/ppapi/tools/pepper_hash_for_uma.cc
@@ -0,0 +1,20 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <stdio.h>
+#include <string.h>
+
+#include "base/hash.h"
+#include "base/macros.h"
+
+int main(int argc, char **argv) {
+  if (argc != 2) {
+    fprintf(stderr, "Usage: %s <interface_name>", argv[0]);
+    return 1;
+  }
+  uint32 data = base::Hash(argv[1], strlen(argv[1]));
+  int hash = bit_cast<int>(data);
+  printf("%s: %d\n", argv[1], hash);
+  return 0;
+}