Enable AudioDecoder unit tests on Android

media/base/audio_hash.h

Index: media/base/audio_hash.h
diff --git a/media/base/audio_hash.h b/media/base/audio_hash.h
index 83ee901d3c97a29d0a703fd98a446f5c3d4f9e94..5ac1aa267b716565ccdd892719e10c3b377716fd 100644
--- a/media/base/audio_hash.h
+++ b/media/base/audio_hash.h
@@ -43,6 +43,11 @@ class MEDIA_EXPORT AudioHash {
   // Return a string representation of the current hash.
   std::string ToString() const;
 
+  // Compare with another hash value given as string representation.

[DaleCurtis, 2016/02/26 23:31:42]

It's a bit odd having an equivalence test like this since the idea of the audio
hash is supposed to provide tolerance in the first place. That said, we get lots
of these tiny off by 1 errors, so perhaps this is nice.

+  // Returns true if for every bucket the difference between this and
+  // other is less than tolerance.
+  bool IsEquivalent(const std::string& other, double tolerance) const;
+
  private:
   // Storage for the audio hash.  The number of buckets controls the importance
   // of position in the hash.  A higher number reduces the chance of false