[WebLayer] Return correct LayoutInflater in SiteSettingsFragmentImpl

This CL fixes the remaining major known Site Settings issues. This
makes the fake settings Activity return the correct LayoutInflater,
which fixes two dialogs that used to crash when opening, and fixes
several theming issues such as incorrect colors or missing checkboxes
or radio controls.

Bug: 1049683
Change-Id: I4d8ab780eac74f3108361a1168e5e41b46935787
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2207814
Commit-Queue: Robbie McElrath <rmcelrath@chromium.org>
Reviewed-by: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#771105}

weblayer/browser/java/org/chromium/weblayer_private/SiteSettingsFragmentImpl.java

@@ -82,9 +82,18 @@ public class SiteSettingsFragmentImpl extends RemoteFragmentImpl {
 
         @Override
         public Object getSystemService(String name) {
+            if (Context.LAYOUT_INFLATER_SERVICE.equals(name)) {
+                return getLayoutInflater();
+            }
             return getEmbedderActivity().getSystemService(name);
         }
 
+        @Override
+        public LayoutInflater getLayoutInflater() {
+            return (LayoutInflater) getBaseContext().getSystemService(
+                    Context.LAYOUT_INFLATER_SERVICE);
+        }
+
         @Override
         public Window getWindow() {
             return getEmbedderActivity().getWindow();