Remove use of IsUIRefreshPhase1Enabled()

This experiment has been defaulted to true for a while now.
Simplified the code.

Bug: 884724
Change-Id: I47fb608b703f292ad8edfe8a91ab9a446fe4d6ec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1554295Reviewed-by: Kurt Horimoto <kkhorimoto@chromium.org>
Commit-Queue: Peter Lee <pkl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#648350}

ios/chrome/browser/ui/fullscreen/fullscreen_egtest.mm

@@ -100,20 +100,7 @@ void AssertURLIs(const GURL& expectedURL) {
   // Initial y scroll positions are set to make room for the toolbar.
   // TODO(crbug.com/618887) Replace use of specific values when API which
   // generates these values is exposed.
-  CGFloat yOffset = 0;
-  if (IsUIRefreshPhase1Enabled()) {
-    if (IsIPadIdiom()) {
-      yOffset = -89.0;
-    } else {
-      yOffset = -48.0;
-    }
-  } else {
-    if (IsIPadIdiom()) {
-      yOffset = -95.0;
-    } else {
-      yOffset = -56.0;
-    }
-  }
+  CGFloat yOffset = IsIPadIdiom() ? -89.0 : -48.0;
   if (@available(iOS 12, *)) {
     // The safe area is included in the top inset as well as the toolbar
     // heights.  Due to crbug.com/903635, however, this only occurs on iOS 12;