Mark RFH::AllowInjectingJavaScriptForAndroidWebView as Android only.

content/public/browser/render_frame_host.h

Index: content/public/browser/render_frame_host.h
diff --git a/content/public/browser/render_frame_host.h b/content/public/browser/render_frame_host.h
index 7e769cb154ad7754de70a7559025c733556dfd8f..d26ec27c1972b2f843215726ec91809707fb7250 100644
--- a/content/public/browser/render_frame_host.h
+++ b/content/public/browser/render_frame_host.h
@@ -35,10 +35,12 @@ class CONTENT_EXPORT RenderFrameHost : public IPC::Listener,
   // Returns nullptr if the IDs do not correspond to a live RenderFrameHost.
   static RenderFrameHost* FromID(int render_process_id, int render_frame_id);
 
+#if defined(OS_ANDROID)
   // Globally allows for injecting JavaScript into the main world. This feature
   // is present only to support Android WebView and must not be used in other
   // configurations.
   static void AllowInjectingJavaScriptForAndroidWebView();
+#endif
 
   // Returns a RenderFrameHost given its accessibility tree ID.
   static RenderFrameHost* FromAXTreeID(int ax_tree_id);