Position cursor on first column on diff chunk navigation

Navigation by clicking on the scroll bar still positions the cursor on
the last column. Only initial position and navigation per keys 'p' and
'n' is changed.

Change-Id: I968171ed1293d722c07f816e3c4a154d23cdac7a
diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/ChunkManager.java b/gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/ChunkManager.java
index 4420940..fed8f91 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/ChunkManager.java
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/ChunkManager.java
@@ -317,7 +317,7 @@
 
         DiffChunkInfo target = chunks.get(res);
         CodeMirror targetCm = host.getCmFromSide(target.getSide());
-        targetCm.setCursor(Pos.create(target.getStart()));
+        targetCm.setCursor(Pos.create(target.getStart(), 0));
         targetCm.focus();
         targetCm.scrollToY(
             targetCm.heightAtLine(target.getStart(), "local") -
diff --git a/gerrit-gwtui/src/main/java/net/codemirror/lib/CodeMirror.java b/gerrit-gwtui/src/main/java/net/codemirror/lib/CodeMirror.java
index fc21532..1c9ad3c 100644
--- a/gerrit-gwtui/src/main/java/net/codemirror/lib/CodeMirror.java
+++ b/gerrit-gwtui/src/main/java/net/codemirror/lib/CodeMirror.java
@@ -204,7 +204,7 @@
     if (lineAtHeight(height - 20) < line) {
       scrollToY(heightAtLine(line, "local") - 0.5 * height);
     }
-    setCursor(Pos.create(line));
+    setCursor(Pos.create(line, 0));
   }
 
   public final native ScrollInfo getScrollInfo() /*-{