Don't update Media.EME.KeySystemSupport UMA for unprefixed EME

media/base/key_systems_unittest.cc

 // Copyright 2013 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 <string>
 #include <vector>
 
 #include "base/logging.h"
 #include "media/base/eme_constants.h"
 #include "media/base/key_system_info.h"
@@ skipping 700 matching lines @@
   UpdateClientKeySystems();
 
   EXPECT_TRUE(IsConcreteSupportedKeySystem(kUsesAes));
   EXPECT_TRUE(IsSupportedKeySystemWithMediaMimeType(
       kVideoWebM, no_codecs(), kUsesAes));
   EXPECT_FALSE(IsConcreteSupportedKeySystem(kExternal));
   EXPECT_FALSE(IsSupportedKeySystemWithMediaMimeType(
       kVideoWebM, no_codecs(), kExternal));
 }
 
+TEST_F(KeySystemsTest, PrefixedKeySystemsUpdate) {
+  EXPECT_TRUE(IsConcreteSupportedKeySystem(kUsesAes));
+  EXPECT_TRUE(PrefixedIsSupportedKeySystemWithMediaMimeType(
+      kVideoWebM, no_codecs(), kUsesAes));
+  EXPECT_TRUE(IsConcreteSupportedKeySystem(kExternal));
+  EXPECT_TRUE(PrefixedIsSupportedKeySystemWithMediaMimeType(
+      kVideoWebM, no_codecs(), kExternal));
+
+  UpdateClientKeySystems();
+
+  EXPECT_TRUE(IsConcreteSupportedKeySystem(kUsesAes));
+  EXPECT_TRUE(PrefixedIsSupportedKeySystemWithMediaMimeType(
+      kVideoWebM, no_codecs(), kUsesAes));
+  EXPECT_FALSE(IsConcreteSupportedKeySystem(kExternal));
+  EXPECT_FALSE(PrefixedIsSupportedKeySystemWithMediaMimeType(
+      kVideoWebM, no_codecs(), kExternal));
+}
+
 }  // namespace media