Allow app_shell embedders to override extensions client interfaces

This includes ExtensionsClient and ExtensionsBrowserClient.

BUG=none
TEST=app_shell_unittests

Review URL: https://codereview.chromium.org/717233003

Cr-Commit-Position: refs/heads/master@{#304946}

4 files changed, 35 insertions, 9 deletions

diff --git a/extensions/shell/browser/shell_browser_main_parts.cc b/extensions/shell/browser/shell_browser_main_parts.cc
index 5651795..7af36498 100644
--- a/extensions/shell/browser/shell_browser_main_parts.cc
+++ b/extensions/shell/browser/shell_browser_main_parts.cc
@@ -143,11 +143,11 @@ void ShellBrowserMainParts::PreMainMessageLoopRun() {
 
   device_client_.reset(new ShellDeviceClient);
 
-  extensions_client_.reset(new ShellExtensionsClient());
+  extensions_client_.reset(CreateExtensionsClient());
   ExtensionsClient::Set(extensions_client_.get());
 
   extensions_browser_client_.reset(
-      new ShellExtensionsBrowserClient(browser_context_.get()));
+      CreateExtensionsBrowserClient(browser_context_.get()));
   ExtensionsBrowserClient::Set(extensions_browser_client_.get());
 
   omaha_query_params_delegate_.reset(new ShellOmahaQueryParamsDelegate);
@@ -252,6 +252,15 @@ void ShellBrowserMainParts::PostDestroyThreads() {
 #endif
 }
 
+ExtensionsClient* ShellBrowserMainParts::CreateExtensionsClient() {
+  return new ShellExtensionsClient();
+}
+
+ExtensionsBrowserClient* ShellBrowserMainParts::CreateExtensionsBrowserClient(
+    content::BrowserContext* context) {
+  return new ShellExtensionsBrowserClient(context);
+}
+
 void ShellBrowserMainParts::CreateExtensionSystem() {
   DCHECK(browser_context_);
   extension_system_ = static_cast<ShellExtensionSystem*>(
diff --git a/extensions/shell/browser/shell_browser_main_parts.h b/extensions/shell/browser/shell_browser_main_parts.h
index 9bce5f0..29032b1 100644
--- a/extensions/shell/browser/shell_browser_main_parts.h
+++ b/extensions/shell/browser/shell_browser_main_parts.h
@@ -14,6 +14,7 @@
 #include "ui/aura/window_tree_host_observer.h"
 
 namespace content {
+class BrowserContext;
 class DevToolsHttpHandler;
 struct MainFunctionParams;
 }
@@ -30,11 +31,11 @@ namespace extensions {
 
 class AppWindowClient;
 class DesktopController;
+class ExtensionsBrowserClient;
+class ExtensionsClient;
 class ShellBrowserContext;
 class ShellBrowserMainDelegate;
 class ShellDeviceClient;
-class ShellExtensionsBrowserClient;
-class ShellExtensionsClient;
 class ShellExtensionSystem;
 class ShellOAuth2TokenService;
 class ShellOmahaQueryParamsDelegate;
@@ -65,6 +66,13 @@ class ShellBrowserMainParts : public content::BrowserMainParts {
   void PostMainMessageLoopRun() override;
   void PostDestroyThreads() override;
 
+ protected:
+  // app_shell embedders may need custom extensions client interfaces.
+  // This class takes ownership of the returned objects.
+  virtual ExtensionsClient* CreateExtensionsClient();
+  virtual ExtensionsBrowserClient* CreateExtensionsBrowserClient(
+      content::BrowserContext* context);
+
  private:
   // Creates and initializes the ExtensionSystem.
   void CreateExtensionSystem();
@@ -77,8 +85,8 @@ class ShellBrowserMainParts : public content::BrowserMainParts {
   scoped_ptr<ShellBrowserContext> browser_context_;
   scoped_ptr<ShellDeviceClient> device_client_;
   scoped_ptr<AppWindowClient> app_window_client_;
-  scoped_ptr<ShellExtensionsClient> extensions_client_;
-  scoped_ptr<ShellExtensionsBrowserClient> extensions_browser_client_;
+  scoped_ptr<ExtensionsClient> extensions_client_;
+  scoped_ptr<ExtensionsBrowserClient> extensions_browser_client_;
   scoped_ptr<net::NetLog> net_log_;
   scoped_ptr<content::DevToolsHttpHandler> devtools_http_handler_;
   scoped_ptr<ShellOmahaQueryParamsDelegate> omaha_query_params_delegate_;
diff --git a/extensions/shell/renderer/shell_content_renderer_client.cc b/extensions/shell/renderer/shell_content_renderer_client.cc
index 216eac6..a56c009 100644
--- a/extensions/shell/renderer/shell_content_renderer_client.cc
+++ b/extensions/shell/renderer/shell_content_renderer_client.cc
@@ -79,7 +79,7 @@ ShellContentRendererClient::~ShellContentRendererClient() {
 void ShellContentRendererClient::RenderThreadStarted() {
   RenderThread* thread = RenderThread::Get();
 
-  extensions_client_.reset(new ShellExtensionsClient);
+  extensions_client_.reset(CreateExtensionsClient());
   ExtensionsClient::Set(extensions_client_.get());
 
   extensions_renderer_client_.reset(new ShellExtensionsRendererClient);
@@ -189,4 +189,8 @@ ShellContentRendererClient::CreateBrowserPluginDelegate(
   }
 }
 
+ExtensionsClient* ShellContentRendererClient::CreateExtensionsClient() {
+  return new ShellExtensionsClient;
+}
+
 }  // namespace extensions
diff --git a/extensions/shell/renderer/shell_content_renderer_client.h b/extensions/shell/renderer/shell_content_renderer_client.h
index 6f62398..b86fa0e 100644
--- a/extensions/shell/renderer/shell_content_renderer_client.h
+++ b/extensions/shell/renderer/shell_content_renderer_client.h
@@ -14,7 +14,7 @@ namespace extensions {
 
 class Dispatcher;
 class DispatcherDelegate;
-class ShellExtensionsClient;
+class ExtensionsClient;
 class ShellExtensionsRendererClient;
 class ShellRendererMainDelegate;
 
@@ -52,8 +52,13 @@ class ShellContentRendererClient : public content::ContentRendererClient {
       const std::string& mime_type,
       const GURL& original_url) override;
 
+ protected:
+  // app_shell embedders may need custom extensions client interfaces.
+  // This class takes ownership of the returned object.
+  virtual ExtensionsClient* CreateExtensionsClient();
+
  private:
-  scoped_ptr<ShellExtensionsClient> extensions_client_;
+  scoped_ptr<ExtensionsClient> extensions_client_;
   scoped_ptr<ShellExtensionsRendererClient> extensions_renderer_client_;
   scoped_ptr<DispatcherDelegate> extension_dispatcher_delegate_;
   scoped_ptr<Dispatcher> extension_dispatcher_;