Remove 'Loading...' title - redundant with the spinner

Also center the text message.
Change: 139498679

tensorflow/tensorboard/components/vz_projector/logging.ts

@@ -34,8 +34,9 @@ export function setDomContainer(domElement: HTMLElement) {
  * @param showCloseButton If true, the dialog will have a close button.
  * @return The id of the message.
  */
-export function setModalMessage(msg: string, id: string = null,
-    title = 'Loading...', showCloseButton = false): string {
+export function setModalMessage(
+    msg: string, id: string = null, title = null,
+    showCloseButton = false): string {
   if (dom == null) {
     console.warn('Can\'t show modal message before the dom is initialized');
     return;

tensorflow/tensorboard/components/vz_projector/vz-projector.html

@@ -145,6 +145,7 @@ limitations under the License.
 }
 
 #notify-msgs {
+  text-align: center;
   display: block;
 }