DevTools: android shouldn't depend on devtools frontend

content/public/browser/devtools_frontend_host.h

Index: content/public/browser/devtools_frontend_host.h
diff --git a/content/public/browser/devtools_frontend_host.h b/content/public/browser/devtools_frontend_host.h
index c7acf6ae63c4e3187eeccebfc2fa079198984cdb..597476dfacaf8a14d141cb477dd82030c47ebbdd 100644
--- a/content/public/browser/devtools_frontend_host.h
+++ b/content/public/browser/devtools_frontend_host.h
@@ -19,6 +19,7 @@ class RenderFrameHost;
 // which is implemented by the embedder.
 // This allows us to avoid exposing DevTools frontend messages through
 // the content public API.
+// Note: DevToolsFrontendHost is not supported on Android.
 class DevToolsFrontendHost {
  public:
   using HandleMessageCallback = base::Callback<void(const std::string&)>;