Improve GCM enum switch type safety

google_apis/gcm/engine/unregistration_request.cc

Index: google_apis/gcm/engine/unregistration_request.cc
diff --git a/google_apis/gcm/engine/unregistration_request.cc b/google_apis/gcm/engine/unregistration_request.cc
index c0b444e709b74bd6198f2dcca9d362f489bd47d3..15c8d883fa39dc806c2475555f849dd26c8b89fa 100644
--- a/google_apis/gcm/engine/unregistration_request.cc
+++ b/google_apis/gcm/engine/unregistration_request.cc
@@ -36,6 +36,29 @@ const char kDeleteValue[] = "true";
 const char kDeviceIdKey[] = "device";
 const char kLoginHeader[] = "AidLogin";
 
+// Determines whether to retry based on the status of the last request.
+bool ShouldRetryWithStatus(UnregistrationRequest::Status status) {
+  switch (status) {
+    case UnregistrationRequest::URL_FETCHING_FAILED:
+    case UnregistrationRequest::NO_RESPONSE_BODY:
+    case UnregistrationRequest::RESPONSE_PARSING_FAILED:
+    case UnregistrationRequest::INCORRECT_APP_ID:
+    case UnregistrationRequest::SERVICE_UNAVAILABLE:
+    case UnregistrationRequest::INTERNAL_SERVER_ERROR:
+    case UnregistrationRequest::HTTP_NOT_OK:
+      return true;
+    case UnregistrationRequest::SUCCESS:
+    case UnregistrationRequest::INVALID_PARAMETERS:
+    case UnregistrationRequest::UNKNOWN_ERROR:
+    case UnregistrationRequest::REACHED_MAX_RETRIES:
+      return false;
+    case UnregistrationRequest::UNREGISTRATION_STATUS_COUNT:
+      NOTREACHED();
+      break;
+  }
+  return false;
+}
+
 }  // namespace
 
 UnregistrationRequest::RequestInfo::RequestInfo(uint64_t android_id,
@@ -177,7 +200,7 @@ void UnregistrationRequest::RetryWithBackoff() {
 void UnregistrationRequest::OnURLFetchComplete(const net::URLFetcher* source) {
   UnregistrationRequest::Status status = ParseResponse(source);
 
-  DVLOG(1) << "UnregistrationRequestStauts: " << status;
+  DVLOG(1) << "UnregistrationRequestStatus: " << status;
 
   DCHECK(custom_request_handler_.get());
   custom_request_handler_->ReportUMAs(
@@ -188,13 +211,7 @@ void UnregistrationRequest::OnURLFetchComplete(const net::URLFetcher* source) {
   recorder_->RecordUnregistrationResponse(request_info_.app_id(),
                                           source_to_record_, status);
 
-  if (status == URL_FETCHING_FAILED ||
-      status == HTTP_NOT_OK ||
-      status == NO_RESPONSE_BODY ||
-      status == SERVICE_UNAVAILABLE ||
-      status == INTERNAL_SERVER_ERROR ||
-      status == INCORRECT_APP_ID ||
-      status == RESPONSE_PARSING_FAILED) {
+  if (ShouldRetryWithStatus(status)) {
     if (retries_left_ > 0) {
       RetryWithBackoff();
       return;
@@ -210,9 +227,6 @@ void UnregistrationRequest::OnURLFetchComplete(const net::URLFetcher* source) {
     custom_request_handler_->ReportUMAs(status, 0, base::TimeDelta());
   }
 
-  // status == SUCCESS || INVALID_PARAMETERS || UNKNOWN_ERROR ||
-  //           REACHED_MAX_RETRIES
-
   callback_.Run(status);
 }