NSS Channel ID: don't check ECC support on every socket creation.

crypto/ec_private_key.h

Index: crypto/ec_private_key.h
diff --git a/crypto/ec_private_key.h b/crypto/ec_private_key.h
index 44f754b038c9e30d45dec3545b4779f4c1759b1a..d66601f811934c50fcdd97aaf0c5c463beabc169 100644
--- a/crypto/ec_private_key.h
+++ b/crypto/ec_private_key.h
@@ -34,6 +34,9 @@ class CRYPTO_EXPORT ECPrivateKey {
  public:
   ~ECPrivateKey();
 
+  // Returns whether the system supports elliptic curve cryptography.
+  static bool IsSupported();
+
   // Creates a new random instance. Can return NULL if initialization fails.
   // The created key will use the NIST P-256 curve.
   // TODO(mattm): Add a curve parameter.