Mark ResourceGenerator subtypes as final.

Patch by: bobv
Review by: rjrjr (desk)

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@6014 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/user/src/com/google/gwt/resources/rg/BundleResourceGenerator.java b/user/src/com/google/gwt/resources/rg/BundleResourceGenerator.java
index 579677d..270e84b 100644
--- a/user/src/com/google/gwt/resources/rg/BundleResourceGenerator.java
+++ b/user/src/com/google/gwt/resources/rg/BundleResourceGenerator.java
@@ -25,7 +25,7 @@
 /**
  * This is a special case of ResourceGenerator that handles nested bundles.
  */
-public class BundleResourceGenerator extends AbstractResourceGenerator {
+public final class BundleResourceGenerator extends AbstractResourceGenerator {
 
   @Override
   public String createAssignment(TreeLogger logger, ResourceContext context,
diff --git a/user/src/com/google/gwt/resources/rg/CssResourceGenerator.java b/user/src/com/google/gwt/resources/rg/CssResourceGenerator.java
index bb96a2b..827239a 100644
--- a/user/src/com/google/gwt/resources/rg/CssResourceGenerator.java
+++ b/user/src/com/google/gwt/resources/rg/CssResourceGenerator.java
@@ -102,7 +102,7 @@
 /**
  * Provides implementations of CSSResources.
  */
-public class CssResourceGenerator extends AbstractResourceGenerator {
+public final class CssResourceGenerator extends AbstractResourceGenerator {
   static class ClassRenamer extends CssVisitor {
     private final Map<JMethod, String> actualReplacements = new IdentityHashMap<JMethod, String>();
 
diff --git a/user/src/com/google/gwt/resources/rg/GwtCreateResourceGenerator.java b/user/src/com/google/gwt/resources/rg/GwtCreateResourceGenerator.java
index 8b981f4..a4231a0 100644
--- a/user/src/com/google/gwt/resources/rg/GwtCreateResourceGenerator.java
+++ b/user/src/com/google/gwt/resources/rg/GwtCreateResourceGenerator.java
@@ -27,7 +27,7 @@
 /**
  * Provides implementations of GwtCreateResource.
  */
-public class GwtCreateResourceGenerator extends AbstractResourceGenerator {
+public final class GwtCreateResourceGenerator extends AbstractResourceGenerator {
 
   @Override
   public String createAssignment(TreeLogger logger, ResourceContext context,