Merge setup flow into a single project

[florelis]

Summary of the pull request

This merges all of the projects that make up the setup flow into a single project. This apparently gives us a major performance boost in loading all the pages in the flow

References and relevant issues

Detailed description of the pull request / Additional comments

Moved everything under the DevHome.SetupFlow, except the ComInterop and Elevated* Projects.
Adjusted the namespaces to remove the parts specific to each page. For example, DevHome.SetupFlow.MainPage.Views was merged into DevHome.SetupFlow.Views.
Besides adjusting the usings in all files, the only major change was in the ServiceExtensions.cs as that had a version on each project. I copied all the methods into a single file.

See before / after:

Validation steps performed

PR checklist

• Closes #xxx
• Tests added/passed
• Documentation updated

[florelis]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).

[manodasanW]

I was doing some perf analysis of DevHome and I decided to do some measurements with this change. I can confirm we do see a great improvement with this change. Composite is what I am using as a baseline which is another change I had done to help improve perf. Setup Flow merge also has that change in the experiment I did.

	Composite (ms)	Setup Flow merge (ms)	Diff (ms)
Application Startup	14570	1120	13450
DashboardView Page Load	2740	332.09	2407.91
WhatsNew Page Load	1770	45.31	1724.69
Last Frame load at Startup	15870	2480	13390
SetupFlow Page Load	3640	110.07	3529.93

[AmelBawa-msft]

It's great to see that merging dlls improves the performance 🔥🔥

Should we keep pages (connected components) in separate folders to maintain the original structure but with a single dll? I am thinking maybe having all viewmodels/views/services from diff pages merged together makes the structure a little harder to analyze without context (?)

Example:

tools/
  SetupFlow/
    AppManagement/
    DevDrive/
    etc...

[bbonaby]

just noticed this is still here, we can delete this entire folder. tools/SetupFlow/DevHome.SetupFlow.DevVolume

[florelis]

Weird; I thought I had already deleted it all. Will delete

Edit: I knew I had already deleted it all!

[florelis]

Should we keep pages (connected components) in separate folders to maintain the original structure but with a single dll? I am thinking maybe having all viewmodels/views/services from diff pages merged together makes the structure a little harder to analyze without context (?)

Example:

tools/
  SetupFlow/
    AppManagement/
    DevDrive/
    etc...

I considered it, but thought it may be better to follow the same structure as in the other projects by having the folders for viewmodels, views, services, etc. at the top level. We may lose a bit of being able to see "all of this is related to appmanagement", but I'd think it's easier to see the more global structure or the parallels between how each page works like this.

I can change it if you want, though

[florelis]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).