Bug 496432: static ICON reference should not be disposed.

The static ICON reference in IconColumnLabelProvider is used for all
icon measurement and rendering. If it's disposed by any specific
instance, it will be unusable going forward. Since only one instance
should exist for the entire runtime, it should be safe to leave it.

Change-Id: Id3d947138bb3de737d33b0af46fef8524f92570a
Reviewed-on: https://git.eclipse.org/r/75587
Tested-by: Hudson CI
Reviewed-by: Jeff Johnston <jjohnstn@redhat.com>
(cherry picked from commit 05d5e4706558aa3a408621023b26cef601c01578)
Reviewed-on: https://git.eclipse.org/r/75646
Reviewed-by: Roland Grunberg <rgrunber@redhat.com>
diff --git a/containers/org.eclipse.linuxtools.docker.ui/src/org/eclipse/linuxtools/internal/docker/ui/wizards/ImageSearchPage.java b/containers/org.eclipse.linuxtools.docker.ui/src/org/eclipse/linuxtools/internal/docker/ui/wizards/ImageSearchPage.java
index 3c0a0e2..4ebdffe 100644
--- a/containers/org.eclipse.linuxtools.docker.ui/src/org/eclipse/linuxtools/internal/docker/ui/wizards/ImageSearchPage.java
+++ b/containers/org.eclipse.linuxtools.docker.ui/src/org/eclipse/linuxtools/internal/docker/ui/wizards/ImageSearchPage.java
@@ -454,7 +454,6 @@
 
 		@Override
 		public void dispose() {
-			ICON.dispose();
 			super.dispose();
 		}