JNI+mm: Generate certificate if non-default key type is specified.

webrtc/sdk/objc/Framework/Classes/RTCConfiguration.mm

Index: webrtc/sdk/objc/Framework/Classes/RTCConfiguration.mm
diff --git a/webrtc/sdk/objc/Framework/Classes/RTCConfiguration.mm b/webrtc/sdk/objc/Framework/Classes/RTCConfiguration.mm
index b006319cae43ae81e1556cd9035b9051b1a16b62..dbe7b53034fc655c28ef37c0baf7080c79e86789 100644
--- a/webrtc/sdk/objc/Framework/Classes/RTCConfiguration.mm
+++ b/webrtc/sdk/objc/Framework/Classes/RTCConfiguration.mm
@@ -15,6 +15,7 @@
 #import "RTCIceServer+Private.h"
 #import "WebRTC/RTCLogging.h"
 
+#include "webrtc/base/rtccertificategenerator.h"
 #include "webrtc/base/sslidentity.h"
 
 @implementation RTCConfiguration
@@ -86,15 +87,15 @@
       _iceConnectionReceivingTimeout;
   nativeConfig.ice_backup_candidate_pair_ping_interval =
       _iceBackupCandidatePairPingInterval;
-  if (_keyType == RTCEncryptionKeyTypeECDSA) {
-    std::unique_ptr<rtc::SSLIdentity> identity(
-        rtc::SSLIdentity::Generate(webrtc::kIdentityName, rtc::KT_ECDSA));
-    if (identity) {
-      nativeConfig.certificates.push_back(
-          rtc::RTCCertificate::Create(std::move(identity)));
-    } else {
-      RTCLogWarning(@"Failed to generate ECDSA identity. RSA will be used.");
-    }
+  rtc::KeyType keyType =
+      [[self class] nativeEncryptionKeyTypeForKeyType:_keyType];
+  // Generate non-default certificate.
+  if (keyType != rtc::KT_DEFAULT) {
+    rtc::scoped_refptr<rtc::RTCCertificate> certificate =
+        rtc::RTCCertificateGenerator::GenerateCertificate(
+            rtc::KeyParams(keyType), rtc::Optional<uint64_t>());
+    RTC_CHECK(certificate);

[hbos, 2016/05/12 08:27:08]

Here I still crash though. Since it is converting to the C++ version of a
configuration and it fails, surrounding code does not handle it (like null is
being handled in the java case):
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/libjin...
In this case handling failure without crashing would be a lot of work.

It is my understanding that it failing is more of a theoretical scenario anyway,
like if you run out of memory, or something incredibly rare happens, I think
crashing is fine.

Our test code CHECK that certificates are generated all the time and they don't
fail.

[hbos, 2016/05/12 08:39:08]

Wait let me see if I can make setConfiguration return false and if that code
path already covers failure.

+    nativeConfig.certificates.push_back(certificate);
   }
 
   return nativeConfig;
@@ -215,6 +216,16 @@
   }
 }
 
++ (rtc::KeyType)nativeEncryptionKeyTypeForKeyType:
+    (RTCEncryptionKeyType)keyType {
+  switch (keyType) {
+    case RTCEncryptionKeyTypeRSA:
+      return rtc::KT_RSA;
+    case RTCEncryptionKeyTypeECDSA:
+      return rtc::KT_ECDSA;
+  }
+}
+
 + (RTCTcpCandidatePolicy)tcpCandidatePolicyForNativePolicy:
     (webrtc::PeerConnectionInterface::TcpCandidatePolicy)nativePolicy {
   switch (nativePolicy) {