webauthn: add some additional caBLE logging.

For now it's useful to be able to see the newly added status feedback in
the logcat for debugging. This uses LOG(ERROR) because I think that INFO
gets stripped from some official builds.

BUG=1002262

Change-Id: I91e6597ff848f1f48cb70c160a6642fd78ac789e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2530834
Commit-Queue: Adam Langley <agl@chromium.org>
Commit-Queue: Martin Kreichgauer <martinkr@google.com>
Auto-Submit: Adam Langley <agl@chromium.org>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
Cr-Commit-Position: refs/heads/master@{#826044}

chrome/android/features/cablev2_authenticator/native/cablev2_authenticator_android.cc

@@ -237,6 +237,7 @@ class AndroidPlatform : public device::cablev2::authenticator::Platform {
 
   void OnStatus(Status status) override {
     DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+    LOG(ERROR) << __func__ << " " << static_cast<int>(status);
 
     if (!cable_authenticator_) {
       return;
@@ -247,6 +248,9 @@ class AndroidPlatform : public device::cablev2::authenticator::Platform {
   }
 
   void OnCompleted(base::Optional<Error> maybe_error) override {
+    LOG(ERROR) << __func__ << " "
+               << (maybe_error ? static_cast<int>(*maybe_error) : -1);
+
     // The transaction might fail before interactive mode, thus
     // |cable_authenticator_| may be empty.
     if (cable_authenticator_) {