Allow setContentDecryptionModule() to get called when setting is done.

media/base/test_helpers.h

Index: media/base/test_helpers.h
diff --git a/media/base/test_helpers.h b/media/base/test_helpers.h
index 8dc38958f5d2a0605b435d9f599e20bb17fd8ab5..b5c14b8be0063f5205a35758c742f20d85d5cd83 100644
--- a/media/base/test_helpers.h
+++ b/media/base/test_helpers.h
@@ -125,6 +125,20 @@ scoped_refptr<DecoderBuffer> CreateFakeVideoBufferForTest(
 bool VerifyFakeVideoBufferForTest(const scoped_refptr<DecoderBuffer>& buffer,
                                   const VideoDecoderConfig& config);
 
+// Used to verify that the number of calls to A() match the number of calls to
+// B() and that the calls happen in pairs (e.g. B() called after every A()
+// call). There may be any number of pairs (including 0).
+class MatchingCallbackVerifier {
+ public:
+  MatchingCallbackVerifier();
+  ~MatchingCallbackVerifier();
+  void A();

[ddorwin, 2014/08/08 21:15:26]

nit: I wonder if this should be "RecordACalled" or "RecordA"

[jrummell, 2014/08/08 23:39:59]

Done.

+  void B();
+
+ private:
+  bool expecting_B_;

[ddorwin, 2014/08/08 21:15:26]

nit: 'b'

[jrummell, 2014/08/08 23:39:59]

Done.

+};
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_TEST_HELPERS_H_