From 87fb6baaa7c8e16e8cef14730822bcca763b61af Mon Sep 17 00:00:00 2001
From: samuelmaddock <samuel.maddock@gmail.com>
Date: Sun, 16 Feb 2020 19:25:08 -0500
Subject: [PATCH] fix(extensions): devtools now open for background pages

---
 .../browser/api/electron_api_web_contents.cc  | 55 +++++++++++++++++--
 shell/browser/api/electron_api_web_contents.h |  2 +-
 2 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/shell/browser/api/electron_api_web_contents.cc b/shell/browser/api/electron_api_web_contents.cc
index 1cb8bf5fdacd8..04d7daf6197ff 100644
--- a/shell/browser/api/electron_api_web_contents.cc
+++ b/shell/browser/api/electron_api_web_contents.cc
@@ -114,6 +114,7 @@
 #endif
 
 #if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
+#include "extensions/browser/view_type_utils.h"
 #include "shell/browser/extensions/electron_extension_web_contents_observer.h"
 #endif
 
@@ -374,21 +375,56 @@ base::string16 GetDefaultPrinterAsync() {
 
 }  // namespace
 
+#if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
+
+WebContents::Type GetTypeFromViewType(extensions::ViewType view_type) {
+  switch (view_type) {
+    case extensions::VIEW_TYPE_EXTENSION_BACKGROUND_PAGE:
+      return WebContents::Type::BACKGROUND_PAGE;
+
+    case extensions::VIEW_TYPE_APP_WINDOW:
+    case extensions::VIEW_TYPE_COMPONENT:
+    case extensions::VIEW_TYPE_EXTENSION_DIALOG:
+    case extensions::VIEW_TYPE_EXTENSION_POPUP:
+    case extensions::VIEW_TYPE_BACKGROUND_CONTENTS:
+    case extensions::VIEW_TYPE_EXTENSION_GUEST:
+    case extensions::VIEW_TYPE_TAB_CONTENTS:
+    case extensions::VIEW_TYPE_INVALID:
+      return WebContents::Type::REMOTE;
+  }
+}
+
+#endif
+
 WebContents::WebContents(v8::Isolate* isolate,
                          content::WebContents* web_contents)
     : content::WebContentsObserver(web_contents),
       type_(Type::REMOTE),
       weak_factory_(this) {
-  web_contents->SetUserAgentOverride(GetBrowserContext()->GetUserAgent(),
-                                     false);
-  Init(isolate);
-  AttachAsUserData(web_contents);
-  InitZoomController(web_contents, gin::Dictionary::CreateEmpty(isolate));
 #if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
+  // WebContents created by extension host will have valid ViewType set.
+  // Must reassign type prior to calling 'Init'.
+  extensions::ViewType view_type = extensions::GetViewType(web_contents);
+  if (view_type != extensions::VIEW_TYPE_INVALID) {
+    type_ = GetTypeFromViewType(view_type);
+
+    // Allow toggling DevTools for background pages
+    // TODO(samuelmaddock): this causes a crash on shutdown
+    Observe(web_contents);
+    InitWithWebContents(web_contents, GetBrowserContext(), IsGuest());
+    managed_web_contents()->GetView()->SetDelegate(this);
+  }
+
   extensions::ElectronExtensionWebContentsObserver::CreateForWebContents(
       web_contents);
   script_executor_.reset(new extensions::ScriptExecutor(web_contents));
 #endif
+
+  web_contents->SetUserAgentOverride(GetBrowserContext()->GetUserAgent(),
+                                     false);
+  Init(isolate);
+  AttachAsUserData(web_contents);
+  InitZoomController(web_contents, gin::Dictionary::CreateEmpty(isolate));
   registry_.AddInterface(base::BindRepeating(&WebContents::BindElectronBrowser,
                                              base::Unretained(this)));
   bindings_.set_connection_error_handler(base::BindRepeating(
@@ -1259,6 +1295,7 @@ void WebContents::DevToolsFocused() {
 void WebContents::DevToolsOpened() {
   v8::Locker locker(isolate());
   v8::HandleScope handle_scope(isolate());
+  DCHECK(managed_web_contents());
   auto handle =
       FromOrCreate(isolate(), managed_web_contents()->GetDevToolsWebContents());
   devtools_web_contents_.Reset(isolate(), handle.ToV8());
@@ -1576,6 +1613,8 @@ void WebContents::OpenDevTools(gin_helper::Arguments* args) {
       options.Get("activate", &activate);
     }
   }
+
+  DCHECK(managed_web_contents());
   managed_web_contents()->SetDockState(state);
   managed_web_contents()->ShowDevTools(activate);
 }
@@ -1584,6 +1623,7 @@ void WebContents::CloseDevTools() {
   if (type_ == Type::REMOTE)
     return;
 
+  DCHECK(managed_web_contents());
   managed_web_contents()->CloseDevTools();
 }
 
@@ -1591,6 +1631,7 @@ bool WebContents::IsDevToolsOpened() {
   if (type_ == Type::REMOTE)
     return false;
 
+  DCHECK(managed_web_contents());
   return managed_web_contents()->IsDevToolsViewShowing();
 }
 
@@ -1598,6 +1639,7 @@ bool WebContents::IsDevToolsFocused() {
   if (type_ == Type::REMOTE)
     return false;
 
+  DCHECK(managed_web_contents());
   return managed_web_contents()->GetView()->IsDevToolsViewFocused();
 }
 
@@ -1606,6 +1648,7 @@ void WebContents::EnableDeviceEmulation(
   if (type_ == Type::REMOTE)
     return;
 
+  DCHECK(web_contents());
   auto* frame_host = web_contents()->GetMainFrame();
   if (frame_host) {
     auto* widget_host =
@@ -1621,6 +1664,7 @@ void WebContents::DisableDeviceEmulation() {
   if (type_ == Type::REMOTE)
     return;
 
+  DCHECK(web_contents());
   auto* frame_host = web_contents()->GetMainFrame();
   if (frame_host) {
     auto* widget_host =
@@ -1646,6 +1690,7 @@ void WebContents::InspectElement(int x, int y) {
   if (!enable_devtools_)
     return;
 
+  DCHECK(managed_web_contents());
   if (!managed_web_contents()->GetDevToolsWebContents())
     OpenDevTools(nullptr);
   managed_web_contents()->InspectElement(x, y);
diff --git a/shell/browser/api/electron_api_web_contents.h b/shell/browser/api/electron_api_web_contents.h
index 3777df745f05f..4218944b5667f 100644
--- a/shell/browser/api/electron_api_web_contents.h
+++ b/shell/browser/api/electron_api_web_contents.h
@@ -97,7 +97,7 @@ class WebContents : public gin_helper::TrackableObject<WebContents>,
                     public mojom::ElectronBrowser {
  public:
   enum class Type {
-    BACKGROUND_PAGE,  // A DevTools extension background page.
+    BACKGROUND_PAGE,  // An extension background page.
     BROWSER_WINDOW,   // Used by BrowserWindow.
     BROWSER_VIEW,     // Used by BrowserView.
     REMOTE,           // Thin wrap around an existing WebContents.