First step in enabling creating tabs without an Activity on Android.

content/public/browser/content_browser_client.cc

Index: content/public/browser/content_browser_client.cc
diff --git a/content/public/browser/content_browser_client.cc b/content/public/browser/content_browser_client.cc
index acacd9850ca0507b98dbace2a9d72bc5eea76747..8f3d06c1edb4a140a334f6c7aa6f8b5d4f4ef25e 100644
--- a/content/public/browser/content_browser_client.cc
+++ b/content/public/browser/content_browser_client.cc
@@ -342,11 +342,6 @@ ContentBrowserClient::GetPresentationServiceDelegate(
   return nullptr;
 }
 
-WebContents* ContentBrowserClient::OpenURL(BrowserContext* browser_context,
-                                           const OpenURLParams& params) {
-  return nullptr;
-}
-
 #if defined(OS_WIN)
 const wchar_t* ContentBrowserClient::GetResourceDllName() {
   return nullptr;