Split ExtensionSystem interface from ExtensionSystemImpl implementation, part 1.

chrome/browser/extensions/extension_view_host.cc

Index: chrome/browser/extensions/extension_view_host.cc
diff --git a/chrome/browser/extensions/extension_view_host.cc b/chrome/browser/extensions/extension_view_host.cc
index b78d5facbf21940c152b4b417a90f573a67633c6..e0932d27f84f6bf90fdafb2b14f2a76842e98ce8 100644
--- a/chrome/browser/extensions/extension_view_host.cc
+++ b/chrome/browser/extensions/extension_view_host.cc
@@ -6,7 +6,6 @@
 
 #include "base/strings/string_piece.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/window_controller.h"
 #include "chrome/browser/file_select_helper.h"
 #include "chrome/browser/platform_util.h"
@@ -18,6 +17,7 @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
+#include "extensions/browser/extension_system.h"
 #include "extensions/browser/runtime_data.h"
 #include "grit/browser_resources.h"
 #include "ui/base/resource/resource_bundle.h"
@@ -139,7 +139,7 @@ void ExtensionViewHost::OnDocumentAvailable() {
 }
 
 void ExtensionViewHost::LoadInitialURL() {
-  if (!ExtensionSystem::GetForBrowserContext(browser_context())->
+  if (!ExtensionSystem::Get(browser_context())->
           runtime_data()->IsBackgroundPageReady(extension())) {
     // Make sure the background page loads before any others.
     registrar()->Add(this,
@@ -320,7 +320,7 @@ void ExtensionViewHost::Observe(int type,
                                 const content::NotificationSource& source,
                                 const content::NotificationDetails& details) {
   if (type == chrome::NOTIFICATION_EXTENSION_BACKGROUND_PAGE_READY) {
-    DCHECK(ExtensionSystem::GetForBrowserContext(browser_context())->
+    DCHECK(ExtensionSystem::Get(browser_context())->
                runtime_data()->IsBackgroundPageReady(extension()));
     LoadInitialURL();
     return;