Always auto-configure pool metadata providers

Import DataSourcePoolMetadataProvidersConfiguration from
DataSourceAutoConfiguration so that PoolMetadataProviders are configured
even if actuator is not used.

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/DataSourceMetricsAutoConfiguration.java

@@ -25,9 +25,7 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.metadata.DataSourcePoolMetadataProvider;
-import org.springframework.boot.autoconfigure.jdbc.metadata.DataSourcePoolMetadataProvidersConfiguration;
 import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Import;
 
 /**
  * {@link EnableAutoConfiguration Auto-configuration} that provides metrics on dataSource
@@ -38,7 +36,6 @@ import org.springframework.context.annotation.Import;
  */
 @ConditionalOnBean(DataSource.class)
 @AutoConfigureAfter(DataSourceAutoConfiguration.class)
-@Import(DataSourcePoolMetadataProvidersConfiguration.class)
 public class DataSourceMetricsAutoConfiguration {
 
 	@Bean

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/DataSourceMetricsAutoConfigurationTests.java

@@ -32,6 +32,7 @@ import org.springframework.boot.actuate.endpoint.PublicMetrics;
 import org.springframework.boot.actuate.metrics.Metric;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
+import org.springframework.boot.autoconfigure.jdbc.metadata.DataSourcePoolMetadataProvidersConfiguration;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -136,7 +137,8 @@ public class DataSourceMetricsAutoConfigurationTests {
 		if (config.length > 0) {
 			this.context.register(config);
 		}
-		this.context.register(DataSourceMetricsAutoConfiguration.class);
+		this.context.register(DataSourcePoolMetadataProvidersConfiguration.class,
+				DataSourceMetricsAutoConfiguration.class);
 		this.context.refresh();
 	}
 

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfiguration.java

@@ -30,6 +30,7 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.SpringBootCondition;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceInitializerPostProcessor.Registrar;
+import org.springframework.boot.autoconfigure.jdbc.metadata.DataSourcePoolMetadataProvidersConfiguration;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
@@ -54,7 +55,7 @@ import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
 @Configuration
 @ConditionalOnClass({ DataSource.class, EmbeddedDatabaseType.class })
 @EnableConfigurationProperties(DataSourceProperties.class)
-@Import(Registrar.class)
+@Import({ Registrar.class, DataSourcePoolMetadataProvidersConfiguration.class })
 public class DataSourceAutoConfiguration {
 
 	/**