Rewrite TwoLineTitleView to use autolayout

[amgleitman]

Platforms Impacted

• iOS
• macOS

Description of changes

This rewrite of TwoLineTitleView makes everything controlled by autolayout, which makes responding to things like screen rotations and content size changes much, much easier. No more manual refreshing! 🎉

This also resolves the bug that made microsoft#1699 and microsoft#1731 incompatible, so we can bring this back as well.

There are several notable changes we made here:

• We no longer use EasyTapButton.
  • Although EasyTapButton will register touches in a minimum area of 44x44, it'll never hear about it if it has a superview that's smaller in either dimension. We use d63c26b to ensure that minimum area.
  • We originally wanted to use a single EasyTapButton as a container view between the TwoLineTitleView and containingStackView, but for some strange reason the button wouldn't register taps. We got around this by overriding the touches... methods from UIResponder. There's no architectural overhead here since UIView extends UIResponder.
• As per a closer look at the design spec, the title and subtitle now use 16x16 and 12x12 chevrons respectively. We previously leaned on the padding on the images, but this is now handled by the spacing inherent to UIStackView. As such, we no longer need the 20x20 chevrons, so we can get rid of them.
• One noticeable visual change for center-aligned titles (as per another closer look at the design spec) is that we now treat each line as a single unit. For more information, see the third and fourth examples under "Made from UINavigationItem" in the verification screenshots. Making this option configurable can be added as an option later if there's an ask for it.

Verification

Visual Verification

Large content size	2XL content size

Pull request checklist

This PR has considered:

• Light and Dark appearances
• iOS supported versions (all major versions greater than or equal current target deployment version)
• VoiceOver and Keyboard Accessibility
• Internationalization and Right to Left layouts
• Different resolutions (1x, 2x, 3x)
• Size classes and window sizes (iPhone vs iPad, notched devices, multitasking, different window sizes, etc)
• iPad Pointer interaction
• SwiftUI consumption (validation or new demo scenarios needed)
• Objective-C exposure (provide it only if needed)

[huwilkes]

Couldn't you just hide the subtitleContainer instead of removing all the subviews and then adding them back?

[huwilkes]

Does titleLeadingImageView.image change between lines 297 and 298, or could you just add it in setupTitleLine? The trailing image is added there, and it would be better to just add them all in one place, in order, instead of add two of them, and later insert one into the front.

[amgleitman]

titleLeadingImageView.image doesn't change, but structuring it this way allows setupTitleLine to also be responsible for the initial clearing out of the stack views. Also, adding leading image view infrastructure to setupTitleLine results in a binary size increase of about 128 bytes.

At the end of the day, I don't think this should be a blocking change, so I'm gonna go with this as is.