Fix build failure

Fixing #5939 lead to a build failure as OAuth2 related configuration was
defined twice. This is also related to #5973.

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/client/OAuth2ProtectedResourceDetailsConfiguration.java

+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure.security.oauth2.client;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+import org.springframework.security.oauth2.client.token.grant.code.AuthorizationCodeResourceDetails;
+
+/**
+ * Shared {@link AuthorizationCodeResourceDetails} configuration.
+ *
+ * @author Stephane Nicoll
+ */
+@Configuration
+class OAuth2ProtectedResourceDetailsConfiguration {
+
+	@Bean
+	@ConfigurationProperties("security.oauth2.client")
+	@Primary
+	public AuthorizationCodeResourceDetails oauth2RemoteResource() {
+		return new AuthorizationCodeResourceDetails();
+	}
+
+}

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/client/OAuth2RestOperationsConfiguration.java

@@ -35,6 +35,7 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ConditionContext;
 import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
 import org.springframework.context.annotation.Primary;
 import org.springframework.context.annotation.Scope;
 import org.springframework.context.annotation.ScopedProxyMode;
@@ -47,7 +48,6 @@ import org.springframework.security.oauth2.client.filter.OAuth2ClientContextFilt
 import org.springframework.security.oauth2.client.token.AccessTokenRequest;
 import org.springframework.security.oauth2.client.token.DefaultAccessTokenRequest;
 import org.springframework.security.oauth2.client.token.grant.client.ClientCredentialsResourceDetails;
-import org.springframework.security.oauth2.client.token.grant.code.AuthorizationCodeResourceDetails;
 import org.springframework.security.oauth2.common.DefaultOAuth2AccessToken;
 import org.springframework.security.oauth2.config.annotation.web.configuration.EnableOAuth2Client;
 import org.springframework.security.oauth2.config.annotation.web.configuration.OAuth2ClientConfiguration;
@@ -88,16 +88,9 @@ public class OAuth2RestOperationsConfiguration {
 	@Configuration
 	@ConditionalOnBean(OAuth2ClientConfiguration.class)
 	@ConditionalOnWebApplication
+	@Import(OAuth2ProtectedResourceDetailsConfiguration.class)
 	protected static class SessionScopedConfiguration {
 
-		@Bean
-		@ConfigurationProperties("security.oauth2.client")
-		@Primary
-		public AuthorizationCodeResourceDetails oauth2RemoteResource() {
-			AuthorizationCodeResourceDetails details = new AuthorizationCodeResourceDetails();
-			return details;
-		}
-
 		@Bean
 		public FilterRegistrationBean oauth2ClientFilterRegistration(
 				OAuth2ClientContextFilter filter, SecurityProperties security) {
@@ -133,16 +126,9 @@ public class OAuth2RestOperationsConfiguration {
 	@Configuration
 	@ConditionalOnMissingBean(OAuth2ClientConfiguration.class)
 	@ConditionalOnWebApplication
+	@Import(OAuth2ProtectedResourceDetailsConfiguration.class)
 	protected static class RequestScopedConfiguration {
 
-		@Bean
-		@ConfigurationProperties("security.oauth2.client")
-		@Primary
-		public AuthorizationCodeResourceDetails oauth2RemoteResource() {
-			AuthorizationCodeResourceDetails details = new AuthorizationCodeResourceDetails();
-			return details;
-		}
-
 		@Bean
 		@Scope(value = "request", proxyMode = ScopedProxyMode.INTERFACES)
 		public DefaultOAuth2ClientContext oauth2ClientContext() {