Bug 577040 - Fix cursor positioning in lambda completion

Fix the formatting issue by avoiding going into link mode when lambda
doesn't have parameters.

Change-Id: Idc4ccf49752c63d21776cd033b1398a0127ccfa8
Signed-off-by: Gayan Perera <gayanper@gmail.com>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.ui/+/187285
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Reviewed-by: Lars Vogel <Lars.Vogel@vogella.com>
diff --git a/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/JavaLambdaCompletionProposal.java b/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/JavaLambdaCompletionProposal.java
index 193c9bc..274a5b6 100644
--- a/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/JavaLambdaCompletionProposal.java
+++ b/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/JavaLambdaCompletionProposal.java
@@ -111,7 +111,7 @@
 		int baseOffset= getReplacementOffset();
 		String replacement= getReplacementString();
 
-		if (fArgumentOffsets != null && getTextViewer() != null) {
+		if (fArgumentOffsets != null && fArgumentOffsets.length > 0 && getTextViewer() != null) {
 			try {
 				LinkedModeModel model= new LinkedModeModel();
 				for (int i= 0; i != fArgumentOffsets.length; i++) {