Don't compile code for desktop zoom or GuestViews on mobile platforms.

chromecast/browser/cast_browser_context.cc

Index: chromecast/browser/cast_browser_context.cc
diff --git a/chromecast/browser/cast_browser_context.cc b/chromecast/browser/cast_browser_context.cc
index 4e60ac88952c3f9a61f57d6cc238fdec10181ba0..0fe6501172ef72065c893bef989803262cd07d44 100644
--- a/chromecast/browser/cast_browser_context.cc
+++ b/chromecast/browser/cast_browser_context.cc
@@ -81,11 +81,13 @@ void CastBrowserContext::InitWhileIOAllowed() {
   BrowserContext::Initialize(this, path_);
 }
 
+#if !defined(OS_ANDROID)
 std::unique_ptr<content::ZoomLevelDelegate>
 CastBrowserContext::CreateZoomLevelDelegate(
     const base::FilePath& partition_path) {
   return nullptr;
 }
+#endif  // !defined(OS_ANDROID)
 
 base::FilePath CastBrowserContext::GetPath() const {
   return path_;