Add WebContentsPreferences::From that checks parameter

atom/browser/api/atom_api_browser_window.cc

@@ -115,7 +115,7 @@ BrowserWindow::BrowserWindow(v8::Isolate* isolate,
     // These preferences will be used when the webContent launches new
     // render processes.
     auto* existing_preferences =
-        WebContentsPreferences::FromWebContents(web_contents->web_contents());
+        WebContentsPreferences::From(web_contents->web_contents());
     base::DictionaryValue web_preferences_dict;
     if (mate::ConvertFromV8(isolate, web_preferences.GetHandle(),
                             &web_preferences_dict)) {

atom/browser/api/atom_api_web_contents.cc

@@ -1122,8 +1122,7 @@ void WebContents::LoadURL(const GURL& url, const mate::Dictionary& options) {
   // created after loading a page.
   const auto view = web_contents()->GetRenderWidgetHostView();
   if (view) {
-    WebContentsPreferences* web_preferences =
-        WebContentsPreferences::FromWebContents(web_contents());
+    auto* web_preferences = WebContentsPreferences::From(web_contents());
     std::string color_name;
     if (web_preferences->dict()->GetString(options::kBackgroundColor,
                                            &color_name)) {
@@ -1840,8 +1839,7 @@ void WebContents::OnGetZoomLevel(content::RenderFrameHost* rfh,
 }
 
 v8::Local<v8::Value> WebContents::GetWebPreferences(v8::Isolate* isolate) {
-  WebContentsPreferences* web_preferences =
-      WebContentsPreferences::FromWebContents(web_contents());
+  auto* web_preferences = WebContentsPreferences::From(web_contents());
   if (!web_preferences)
     return v8::Null(isolate);
   return mate::ConvertToV8(isolate, *web_preferences->dict());

atom/browser/api/atom_api_web_view_manager.cc

@@ -34,7 +34,7 @@ void AddGuest(int guest_instance_id,
         ->SetDefaultZoomFactor(zoom_factor);
   }
 
-  WebContentsPreferences::FromWebContents(guest_web_contents)->Merge(options);
+  WebContentsPreferences::From(guest_web_contents)->Merge(options);
 }
 
 void RemoveGuest(content::WebContents* embedder, int guest_instance_id) {

atom/browser/atom_browser_client.cc

@@ -235,8 +235,7 @@ void AtomBrowserClient::OverrideSiteInstanceForNavigation(
   // Do we have an affinity site to manage ?
   std::string affinity;
   auto* web_contents = content::WebContents::FromRenderFrameHost(rfh);
-  auto* web_preferences = web_contents ?
-      WebContentsPreferences::FromWebContents(web_contents) : nullptr;
+  auto* web_preferences = WebContentsPreferences::From(web_contents);
   if (web_preferences &&
       web_preferences->dict()->GetString("affinity", &affinity) &&
       !affinity.empty()) {

atom/browser/native_window_views.cc

@@ -1370,14 +1370,12 @@ void NativeWindowViews::ShowAutofillPopup(
   bool is_offsceen = false;
   bool is_embedder_offscreen = false;
 
-  auto* web_contents_preferences =
-      WebContentsPreferences::FromWebContents(web_contents);
-  if (web_contents_preferences) {
-    const auto* web_preferences = web_contents_preferences->dict();
-
-    web_preferences->GetBoolean("offscreen", &is_offsceen);
+  auto* web_preferences = WebContentsPreferences::From(web_contents);
+  if (web_preferences) {
+    web_preferences->dict()->GetBoolean("offscreen", &is_offsceen);
     int guest_instance_id = 0;
-    web_preferences->GetInteger(options::kGuestInstanceID, &guest_instance_id);
+    web_preferences->dict()->GetInteger(options::kGuestInstanceID,
+                                        &guest_instance_id);
 
     if (guest_instance_id) {
       auto manager = WebViewManager::GetWebViewManager(web_contents);

atom/browser/web_contents_preferences.cc

@@ -105,6 +105,14 @@ content::WebContents* WebContentsPreferences::GetWebContentsFromProcessID(
   return nullptr;
 }
 
+// static
+WebContentsPreferences* WebContentsPreferences::From(
+    content::WebContents* web_contents) {
+  if (!web_contents)
+    return nullptr;
+  return FromWebContents(web_contents);
+}
+
 // static
 void WebContentsPreferences::AppendExtraCommandLineSwitches(
     content::WebContents* web_contents, base::CommandLine* command_line) {

atom/browser/web_contents_preferences.h

@@ -33,6 +33,9 @@ class WebContentsPreferences
   // FIXME(zcbenz): This method does not belong here.
   static content::WebContents* GetWebContentsFromProcessID(int process_id);
 
+  // Get self from WebContents.
+  static WebContentsPreferences* From(content::WebContents* web_contents);
+
   // Append command paramters according to |web_contents|'s preferences.
   static void AppendExtraCommandLineSwitches(
       content::WebContents* web_contents, base::CommandLine* command_line);