crypto: change ECSignatureCreator defaults to match SPDY.

net/spdy/spdy_test_util_spdy3.cc

Index: net/spdy/spdy_test_util_spdy3.cc
diff --git a/net/spdy/spdy_test_util_spdy3.cc b/net/spdy/spdy_test_util_spdy3.cc
index cffd9eb8906c886757340779832ade1deda78110..6598a49927bd8bc5269bf1bf408804745e3c8f6e 100644
--- a/net/spdy/spdy_test_util_spdy3.cc
+++ b/net/spdy/spdy_test_util_spdy3.cc
@@ -63,6 +63,12 @@ class MockECSignatureCreator : public crypto::ECSignatureCreator {
     return true;
   }
 
+  virtual bool DecodeSignature(const std::vector<uint8>& signature,
+                               std::vector<uint8>* out_raw_sig) {
+    *out_raw_sig = signature;
+    return true;
+  }
+
  private:
   crypto::ECPrivateKey* key_;