[Dialogs] Fix incorrect vertical layout for uppercase buttons (materi…

…al-components#9877)

material-components#9411 Description

Making sure layout subviews calculates content size based on the available size, not based on the size of the previous layout calculations. This fixes an issue in which the dialog unexpectedly changed vertical vs horizontal actions layout after the first layout pass (see issue #8434 - b/137070719).

## Before
Actions are laid out vertically - when loaded for the first time, and horizontally thereafter (for instance: after orientation changed, app is sent to the background, etc):

![dialog - actions - uppercase - BEFORE](https://user-images.githubusercontent.com/2329102/76383815-6bb92880-6333-11ea-984d-0e392d433ed4.png)

## After
Actions are laid out horizontally on all layout passes - including the first:

![dialog - actions - uppercase - AFTER](https://user-images.githubusercontent.com/2329102/76383817-6c51bf00-6333-11ea-9892-828abc3d7854.png)

## Issues
Closes #8434 (b/137070719).
PiperOrigin-RevId: 299735842

components/Dialogs/src/MDCAlertController.m

@@ -627,7 +627,7 @@ - (void)viewWillLayoutSubviews {
   if (CGRectGetWidth(self.view.bounds) != _previousLayoutSize.width ||
       CGRectGetHeight(self.view.bounds) != _previousLayoutSize.height) {
     CGSize currentPreferredContentSize = self.preferredContentSize;
-    CGSize contentSize = CGRectStandardize(self.alertView.bounds).size;
+    CGSize contentSize = CGRectInfinite.size;
     CGSize calculatedPreferredContentSize =
         [self.alertView calculatePreferredContentSizeForBounds:contentSize];
 

components/Dialogs/tests/snapshot/MDCAlertControllerActionsTests.m

@@ -68,7 +68,7 @@ - (void)tearDown {
 - (void)sizeTofitContent {
   // Ensure snapshot view size matches actual runtime size of alert
   MDCAlertControllerView *alertView = (MDCAlertControllerView *)self.alertController.view;
-  CGSize preferredContentSize = self.alertController.preferredContentSize;
+  CGSize preferredContentSize = CGRectInfinite.size;
   CGSize bounds = [alertView calculatePreferredContentSizeForBounds:preferredContentSize];
   self.alertController.view.bounds = CGRectMake(0.f, 0.f, bounds.width, bounds.height);
 }