Reuse existing variable

Change-Id: I376093c74cadad26de991318151e19a2ac113b21
Signed-off-by: Mykola Nikishov <mn@mn.com.ua>
diff --git a/bundles/org.eclipse.compare/compare/org/eclipse/compare/contentmergeviewer/TextMergeViewer.java b/bundles/org.eclipse.compare/compare/org/eclipse/compare/contentmergeviewer/TextMergeViewer.java
index a9c9555..b9f8760 100644
--- a/bundles/org.eclipse.compare/compare/org/eclipse/compare/contentmergeviewer/TextMergeViewer.java
+++ b/bundles/org.eclipse.compare/compare/org/eclipse/compare/contentmergeviewer/TextMergeViewer.java
@@ -856,7 +856,7 @@
 				StyledText textWidget = fSourceViewer.getSourceViewer().getTextWidget();
 				if (textWidget != null && !textWidget.isDisposed()) {
 					if (fNeedsValidation) {
-						fSourceViewer.getSourceViewer().getTextWidget().removeVerifyListener(this);
+						textWidget.removeVerifyListener(this);
 						fNeedsValidation = false;
 					}
 					IDocument oldDoc= internalGetDocument(fSourceViewer);