'New' forms: behavior inconsistency
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### Summary
Inconsistency in signaling missing mandatory fields in 'New' forms
### Steps to reproduce
1. Login to gitlab.com
1. Top menu -\> 'New' button. Then follow either of the followings:
+ Scenario 1: Select 'New project'. Do not fill in anything, but just click the **green* 'Create project' button.
+ Scenario 2: Select 'New group'. Do not fill in anything, but just click the **green* 'Create group' button.
+ Scenario 3: Select 'New snippet'. Do not fill in anything.
### Example Project
N/A
### What is the current *bug* behavior?
- Scenario 1: a tooltip with a yellow exclamation mark displays signaling the missing 'Project slug'.
- Scenario 2: 'Group name' and 'Group URL' fields have their borders turned red with red texts below each signaling the errors.
- Scenario 3: 'Create snippet' button remains gray/inactive until user figured out and filled in the mandatory details.
### What is the expected *correct* behavior?
One design/behavior style should apply through out the software.
### Relevant logs and/or screenshots
### Output of checks
This bug happens on GitLab.com
issue