Add Anvil

[aitorvs]

Task/Issue URL: https://app.asana.com/0/414730916066338/1199916263225064/f
Tech Design URL:
CC:

Description:
We've been using Dagger Android for a while and it has been good help. We've also seen some drawbacks moving forward

• it is not easy to replace dependencies for testing, forcing us to create a TestComponent, custom TestRunner and a custom TestApplication
• this also comes with some other problems like circular dependencies when splitting the codebase into multiple modules
• multi (gradle) module is harder to get right with just Dagger and Dagger-Android and we want to start splitting the app little by little

This PR:

• Adds Anvil and remove dagger-android annotation processor
• Creates a gradle module :di that is home to the Dagger components marker (scope) annotations
• Removes the TestApplication and TestComponent
• Adds a a bunch of binding classes under com.duckduckgo.app.di.component
• these files replace the now removed AndroidBindingModule.kt that used the dagger-android annotation processor (DAAP)
• DAAP can't work with Anvil because we need to replace the @Component and @SubComponent with @MergeComponent and @MergeSubComponent correspondingly and so we can't do that for the DAAP-generated code.
• the codee in those files is pretty much the code generated by DAAP
• the con is that we need to do it ourselves now, tho we can easily do this by either copy/paste/replace and/or a file template in AS (I did with a file template)
• the pro is that it is now very clear what is under the hood, and so DI errors are less obscure now (hopefully)

Note:

• full build -> 1min40s
• incremental build -> 20s

Steps to test this PR:

1. App compiles
2. All tests pass
3. updgrade/install the app from this branch
4. verify that every entry that was in the AndroidBindingModule.kt has now a dedicated file in the package com.duckduckgo.app.di.component

• eg. BrowserActivity -> BrowserActivityComponent.kt

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Internal references:

Software Engineering Expectations
Technical Design Template

[aitorvs]

This is how we replace dagger modules for testing with Anvil. No more TestComponent needed

[aitorvs]

@MergeComponent is the anvil-equivalent to dagger @Component. This annotation is what anvil uses to generate the dagger components under the hood.
The scope is not be confused to eg. ActivityScope or Singleton scope-annotations. It simply is a marker class that identifies the dagger component, so that we can later provide modules/dependencies without needing to get access to the dagger component type

[aitorvs]

We should find a better way to do this. This is needed by the ATB e2e tests and it was done in the same manner in the now removed TestComponent.
I will think about this and prob tackle it in a different PR

[aitorvs]

I took the opportunity to bump a patch version here

[marcosholgado]

Good job @aitorvs! 👏

• Made sure we replaced everything within the AndroidBindingModule.
• Tested updating the app, onboarding, bookmarks, fire button, fireproof, location dialog, pixels, tabs, find in page, privacy dashboard, grade animation, broken sites, icon change and notifications.