Candidate: use "Objects.equals" instead of "=="

Errorprone raises the following warning:
"[ReferenceEquality] Comparison using reference equality
instead of value equality".

Change-Id: Iacb207ef0625bb987a08406d4e7461e48fade97f

org.eclipse.jgit/src/org/eclipse/jgit/blame/Candidate.java

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/blame/Candidate.java b/org.eclipse.jgit/src/org/eclipse/jgit/blame/Candidate.java
index ca5370e..ccf99ff 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/blame/Candidate.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/blame/Candidate.java
@@ -12,6 +12,7 @@
 
 import java.io.IOException;
 import java.util.List;
+import java.util.Objects;
 
 import org.eclipse.jgit.blame.ReverseWalk.ReverseCommit;
 import org.eclipse.jgit.diff.Edit;
@@ -269,7 +270,7 @@ private Region clearRegionList() {
 	}
 
 	boolean canMergeRegions(Candidate other) {
-		return sourceCommit == other.sourceCommit
+		return Objects.equals(sourceCommit, other.sourceCommit)
 				&& sourcePath.getPath().equals(other.sourcePath.getPath());
 	}