[remoting] Improve permission wizard appearance

Some tweaks to the MacOS permission wizard:
* Reduced icon size in the dialog (without affecting the dock icon).
  This selects the 64x64 icon from remoting_host.icns.
* Reduced vertical spacing between buttons and text.
* Horizontally centered the "All Set" text within the area occupied by
  the instruction text. Currently, the window does not shrink when the
  text is replaced with shorter text (because resizing the window
  causes it to jump somewhere else).
* Fixed incorrect vertical position of "OK" button on final page.

Bug: 1032157
Change-Id: Iedc9a0640200bc2a4152b931f572d35fb3e76312
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1980973
Auto-Submit: Lambros Lambrou <lambroslambrou@chromium.org>
Commit-Queue: Jamie Walch <jamiewalch@chromium.org>
Reviewed-by: Jamie Walch <jamiewalch@chromium.org>
Cr-Commit-Position: refs/heads/master@{#729402}

remoting/host/mac/permission_wizard.mm

@@ -228,9 +228,12 @@ void PermissionWizard::Impl::OnPermissionCheckResult(bool result) {
   _instructionText.editable = NO;
   _instructionText.preferredMaxLayoutWidth = 400;
 
+  NSString* appPath = [[NSBundle mainBundle] bundlePath];
+  NSImage* iconImage = [[NSWorkspace sharedWorkspace] iconForFile:appPath];
+  [iconImage setSize:NSMakeSize(64, 64)];
   NSImageView* icon = [[[NSImageView alloc] init] autorelease];
   icon.translatesAutoresizingMaskIntoConstraints = NO;
-  icon.image = [[NSApplication sharedApplication] applicationIconImage];
+  icon.image = iconImage;
 
   _cancelButton = [[[NSButton alloc] init] autorelease];
   _cancelButton.translatesAutoresizingMaskIntoConstraints = NO;
@@ -285,7 +288,7 @@ void PermissionWizard::Impl::OnPermissionCheckResult(bool result) {
   iconAndTextStack.alignment = NSLayoutAttributeTop;
   [iconAndTextStack addView:icon inGravity:NSStackViewGravityLeading];
   [iconAndTextStack addView:_instructionText
-                  inGravity:NSStackViewGravityLeading];
+                  inGravity:NSStackViewGravityCenter];
 
   NSStackView* buttonsStack = [[[NSStackView alloc] init] autorelease];
   buttonsStack.translatesAutoresizingMaskIntoConstraints = NO;
@@ -297,10 +300,17 @@ void PermissionWizard::Impl::OnPermissionCheckResult(bool result) {
   [buttonsStack addView:_nextButton inGravity:NSStackViewGravityTrailing];
   [buttonsStack addView:_okButton inGravity:NSStackViewGravityTrailing];
 
+  // Prevent buttonsStack from expanding vertically. This fixes incorrect
+  // vertical placement of OK button in All Set page
+  // (http://crbug.com/1032157). The parent NSStackView was expanding this
+  // view instead of adding space between the gravity-areas.
+  [buttonsStack setHuggingPriority:NSLayoutPriorityDefaultHigh
+                    forOrientation:NSLayoutConstraintOrientationVertical];
+
   NSStackView* mainStack = [[[NSStackView alloc] init] autorelease];
   mainStack.translatesAutoresizingMaskIntoConstraints = NO;
   mainStack.orientation = NSUserInterfaceLayoutOrientationVertical;
-  mainStack.spacing = 20;
+  mainStack.spacing = 12;
   [mainStack addView:iconAndTextStack inGravity:NSStackViewGravityTop];
   [mainStack addView:buttonsStack inGravity:NSStackViewGravityBottom];