GWT/Poly: Default to "Create initial commit" during project creation

Common support cases for our Gerrit admins stems from users creating
projects without an initial empty commit. The absolute vast majority
of end-users do want an initial commit in their newly created projects,
but sometimes misses to check the "Create initial commit"-checkbox in
the UI. When failing to do so, the situation may be a bit problematic
to remedy for the end user since:

* It is not always clear why they cannot push reviews to their newly
created git.
* It is cumbersome to create an empty root commit for casual git users
* Direct push to refs/heads/* is not always permittable

At our company we have yet to see someone creating an empty commit and
do not want it.

Change-Id: I2462e5fb7dbb68b0816ec25fa0b42ad135a2bb68

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/CreateProjectScreen.java

@@ -130,6 +130,7 @@ public class CreateProjectScreen extends Screen {
     addGrid(fp);
 
     emptyCommit = new CheckBox(AdminConstants.I.checkBoxEmptyCommit());
+    emptyCommit.setValue(true);
     permissionsOnly = new CheckBox(AdminConstants.I.checkBoxPermissionsOnly());
     fp.add(emptyCommit);
     fp.add(permissionsOnly);

polygerrit-ui/app/elements/admin/gr-create-project-dialog/gr-create-project-dialog.js

@@ -31,7 +31,7 @@
         value: () => {
           // Set default values for dropdowns.
           return {
-            create_empty_commit: false,
+            create_empty_commit: true,
             permissions_only: false,
           };
         },

polygerrit-ui/app/elements/admin/gr-create-project-dialog/gr-create-project-dialog_test.html

@@ -49,7 +49,7 @@ limitations under the License.
     });
 
     test('default values are populated', () => {
-      assert.isFalse(element.$.initalCommit.bindValue);
+      assert.isTrue(element.$.initalCommit.bindValue);
       assert.isFalse(element.$.parentProject.bindValue);
     });