FOP-2939: Upgrade ant to 1.9.15

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1880454 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/fop-core/pom.xml b/fop-core/pom.xml
index 4c24685..756fb89 100644
--- a/fop-core/pom.xml
+++ b/fop-core/pom.xml
@@ -86,7 +86,7 @@
     <dependency>
       <groupId>org.apache.ant</groupId>
       <artifactId>ant</artifactId>
-      <version>1.9.15</version>
+      <version>${ant.version}</version>
       <scope>provided</scope>
     </dependency>
     <dependency>
diff --git a/fop-events/pom.xml b/fop-events/pom.xml
index a3fd661..7183d49 100644
--- a/fop-events/pom.xml
+++ b/fop-events/pom.xml
@@ -34,7 +34,7 @@
     <dependency>
       <groupId>org.apache.ant</groupId>
       <artifactId>ant</artifactId>
-      <version>1.8.2</version>
+      <version>${ant.version}</version>
     </dependency>
     <dependency>
       <groupId>org.apache.xmlgraphics</groupId>
diff --git a/pom.xml b/pom.xml
index b7881c7..5671e2a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -11,6 +11,7 @@
   <url>http://xmlgraphics.apache.org/fop/</url>
 
   <properties>
+    <ant.version>1.9.15</ant.version>
     <antrun.plugin.version>1.8</antrun.plugin.version>
     <batik.version>1.11.0-SNAPSHOT</batik.version>
     <build.helper.plugin.version>1.9.1</build.helper.plugin.version>