Draft: Combined menu Vue app [RUN ALL RSPEC] [RUN AS-IF-FOSS]

• Requirements (issue)
• Tasks (epic)
• Full Context Spike MR (permanent draft)

All MR parts

• (merged) combined_menu flag feature specs MR
• (merged) Add top level warning to deprecated views MR
• (merged) Introduce top nav helper MR
  • (merged) Finish migrating to top_nav_view_model MR (depends on parent MR)
• (merged) Improve frequent_items style flexibility MR
• (merged) Refactor frequent items into vuex modules
• (merged) Add keep_alive_slots component
  • (merged) Frontend for top nav menu redesign
• (merged) Fix shortcuts for top nav redesign
• (merged) Add missing inheritAttrs: false
• (merged) Add help item to bottom of signed out top nav
• (merged) Fix missing data and class in top_nav_menu_item
• (merged) Fix and unpend all specs which are currently failing with :combined_menu flag on
• (merged) Remove "Switch To" tooltip from top nav
• (merged) Move new_dropdown logic from haml to view_model
• (merged) Update frequent_items to upcoming resp styling
• (merged) Add top_nav_menu_sections component
• (merged) Decouple content-wrapper and content-wrapper-margin
  • (merged) Part 1 - Setup for responsive top nav redesign (depends on parent MR)
    • (merged) Part 2 - Top nav responsive view (depends on parent MR)
• (merged) Change top nav menu icon to 'hamburger'
• (merged) Handle top nav active for project/group
• ...
• Enable combined_menu ff by default

What does this MR do?

Screenshots (strongly suggested)

2021-05-31 We're going responsive!

Closed	Open + Signed out	Open	Open + User dropdown

"New..." subview	"Projects" subview	"Groups" subview

• For the "Projects" subview, I manually duplicated some of the rows to test the scrolling look and feel.

2021-04-22 WIP

Top nav	Responsive

Does this MR meet the acceptance criteria?

Conformity

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  • I have included a changelog entry.
  • I have not included a changelog entry because _____.
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Related to #301143 (closed)