[dogfooding][cleanup] Use static inner class clean up for compare cocde

Using this cleanup brings:
- It reviews the feature
 - For optimization: small memory usage reduction as the outer pointer
is removed

Change-Id: I8f1bdcb09e0e654683c0cb5e26c8370d6a47638e
Signed-off-by: Lars Vogel <Lars.Vogel@vogella.com>
diff --git a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareFilterDescriptor.java b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareFilterDescriptor.java
index b5d2d88..9bb3d5d 100644
--- a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareFilterDescriptor.java
+++ b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareFilterDescriptor.java
@@ -40,7 +40,7 @@
 	private ResourceBundle fResourceBundle;
 	private ImageDescriptor fImageDescriptor;
 
-	private class ConfigurationKeysEnumeration implements Enumeration<String> {
+	private static class ConfigurationKeysEnumeration implements Enumeration<String> {
 
 		private String[] keySet;
 		private int cursor = 0;
diff --git a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareWithOtherResourceDialog.java b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareWithOtherResourceDialog.java
index 4f4103c..8f1d0d5 100644
--- a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareWithOtherResourceDialog.java
+++ b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareWithOtherResourceDialog.java
@@ -76,7 +76,7 @@
 	private int MIN_HEIGHT_WITH_ANCESTOR = 320;
 	private int MIN_HEIGHT_WITHOUT_ANCESTOR = 238;
 
-	private class FileTextDragListener implements DragSourceListener {
+	private static class FileTextDragListener implements DragSourceListener {
 
 		private ContentTypeElement element;
 
@@ -101,7 +101,7 @@
 		}
 	}
 
-	private class FileTextDropListener implements DropTargetListener {
+	private static class FileTextDropListener implements DropTargetListener {
 
 		private ContentTypeElement element;
 		private ResourceTransfer resourceTransfer;
@@ -181,7 +181,7 @@
 
 	}
 
-	private abstract class ContentTypeElement {
+	private abstract static class ContentTypeElement {
 
 		private Button radioButton;
 		protected Button mainButton;
diff --git a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/EditionAction.java b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/EditionAction.java
index 5619280..b68ce8f 100644
--- a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/EditionAction.java
+++ b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/EditionAction.java
@@ -56,7 +56,7 @@
 	 * Implements the IStreamContentAccessor and ITypedElement protocols
 	 * for a Document.
 	 */
-	class DocumentBufferNode implements ITypedElement, IEncodedStreamContentAccessor {
+	static class DocumentBufferNode implements ITypedElement, IEncodedStreamContentAccessor {
 		private static final String UTF_16= "UTF-16"; //$NON-NLS-1$
 		private IDocument fDocument;
 		private IFile fFile;
diff --git a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/ResourceCompareInput.java b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/ResourceCompareInput.java
index 8f4604d..b718f97 100644
--- a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/ResourceCompareInput.java
+++ b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/ResourceCompareInput.java
@@ -175,7 +175,7 @@
 		return fDiffViewer;
 	}
 
-	class SelectAncestorDialog extends MessageDialog {
+	static class SelectAncestorDialog extends MessageDialog {
 		private IResource[] theResources;
 		IResource ancestorResource;
 		IResource leftResource;