Fix error dialog not honoring line breaks

Creating ErrorDialog from Throwable was already formatting error message
nicely because it is setting the css attribute 'whiteSpace' to 'pre'.
Creating ErrorDialog from an error message string was not setting this
css attribute resulting in line break being removed.

Fix this by making both use a private method to create error message
label. Also change the attribute from 'whiteSpace' to 'white-space'
which is the real name.

Change-Id: I5932c3d547b8ab232de2f866d0ad20d968804ee8

gerrit-gwtui/src/main/java/com/google/gerrit/client/ErrorDialog.java

diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/ErrorDialog.java b/gerrit-gwtui/src/main/java/com/google/gerrit/client/ErrorDialog.java
index e880712..8e12575 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/ErrorDialog.java
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/ErrorDialog.java
@@ -88,7 +88,7 @@
   /** Create a dialog box to show a single message string. */
   public ErrorDialog(final String message) {
     this();
-    body.add(new Label(message));
+    body.add(createErrorMsgLabel(message));
   }
 
   /** Create a dialog box to show a single message string. */
@@ -145,12 +145,16 @@
     }
 
     if (msg != null) {
-      final Label m = new Label(msg);
-      m.getElement().getStyle().setProperty("whiteSpace", "pre");
-      body.add(m);
+      body.add(createErrorMsgLabel(msg));
     }
   }
 
+  private Label createErrorMsgLabel(String message) {
+    Label m = new Label(message);
+    m.getElement().getStyle().setProperty("white-space", "pre");
+    return m;
+  }
+
   public ErrorDialog setText(final String t) {
     text.setText(t);
     return this;