Support generation of EC keys using P256 curve and support ECDSA certs.

webrtc/base/sslidentity.h

Index: webrtc/base/sslidentity.h
diff --git a/webrtc/base/sslidentity.h b/webrtc/base/sslidentity.h
index 320fe53d0f5ad01fee6790c469d7ab0276053c4d..78f846b53e3bc7a304640c3cc892800f1acbf512 100644
--- a/webrtc/base/sslidentity.h
+++ b/webrtc/base/sslidentity.h
@@ -117,6 +117,8 @@ struct SSLIdentityParams {
   int not_after;  // in seconds.
 };
 
+enum KeyType { KT_RSA, KT_ECDSA, KT_DEFAULT = KT_RSA };
+
 // Our identity in an SSL negotiation: a keypair and certificate (both
 // with the same public key).
 // This too is pretty much immutable once created.
@@ -127,10 +129,12 @@ class SSLIdentity {
   // subject and issuer name, otherwise a random string will be used.
   // Returns NULL on failure.
   // Caller is responsible for freeing the returned object.
-  static SSLIdentity* Generate(const std::string& common_name);
+  static SSLIdentity* Generate(const std::string& common_name,
+                               KeyType key_type);
 
   // Generates an identity with the specified validity period.
-  static SSLIdentity* GenerateForTest(const SSLIdentityParams& params);
+  static SSLIdentity* GenerateForTest(const SSLIdentityParams& params,
+                                      KeyType key_type);
 
   // Construct an identity from a private key and a certificate.
   static SSLIdentity* FromPEMStrings(const std::string& private_key,