Re-land alexbost's experimental offscreenTabs API.

chrome/browser/extensions/extension_tabs_module.h

Index: chrome/browser/extensions/extension_tabs_module.h
diff --git a/chrome/browser/extensions/extension_tabs_module.h b/chrome/browser/extensions/extension_tabs_module.h
index 944de1c7382c2a8f044a405083464ac82cf22337..037ec3399718faf6ed42b6babea493bfafe8b15c 100644
--- a/chrome/browser/extensions/extension_tabs_module.h
+++ b/chrome/browser/extensions/extension_tabs_module.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -17,12 +17,41 @@
 #include "googleurl/src/gurl.h"
 
 class BackingStore;
+class Extension;
+class GURL;
 class SkBitmap;
+class TabContentsWrapper;
 
 namespace base {
 class DictionaryValue;
 }  // namespace base
 
+namespace content {
+class WebContents;
+}  // namespace content
+
+
+// TODO(jstritar): These helper methods are exposed so the offscreen tabs API
+// can use them. We should remove these once the APIs are combined.
+namespace extensions {
+namespace tabs_module {
+
+// Takes |url_string| and returns a GURL which is either valid and absolute
+// or invalid. If |url_string| is not directly interpretable as a valid (it is
+// likely a relative URL) an attempt is made to resolve it. |extension| is
+// provided so it can be resolved relative to its extension base
+// (chrome-extension://<id>/). Using the source frame url would be more correct,
+// but because the api shipped with urls resolved relative to their extension
+// base, we decided it wasn't worth breaking existing extensions to fix.
+GURL ResolvePossiblyRelativeURL(const std::string& url_string,
+                                const Extension* extension);
+
+// Returns true if |url| is used for testing crashes.
+bool IsCrashURL(const GURL& url);
+
+}  // namespace tabs_module
+}  // namespace extensions
+
 // Windows
 class GetWindowFunction : public SyncExtensionFunction {
   virtual ~GetWindowFunction() {}
@@ -109,8 +138,12 @@ class UpdateTabFunction : public AsyncExtensionFunction,
                           public content::WebContentsObserver {
  public:
   UpdateTabFunction();
- private:
+ protected:
   virtual ~UpdateTabFunction() {}
+  virtual bool UpdateURLIfPresent(base::DictionaryValue* update_props,
+                                  content::WebContents* web_contents,
+                                  bool* is_async);
+ private:
   virtual bool RunImpl() OVERRIDE;
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
   void OnExecuteCodeFinished(int request_id,
@@ -148,7 +181,7 @@ class DetectTabLanguageFunction : public AsyncExtensionFunction,
 };
 class CaptureVisibleTabFunction : public AsyncExtensionFunction,
                                   public content::NotificationObserver {
- private:
+ protected:
   enum ImageFormat {
     FORMAT_JPEG,
     FORMAT_PNG
@@ -159,6 +192,8 @@ class CaptureVisibleTabFunction : public AsyncExtensionFunction,
 
   virtual ~CaptureVisibleTabFunction() {}
   virtual bool RunImpl() OVERRIDE;
+  virtual bool GetTabToCapture(content::WebContents** web_contents,
+                               TabContentsWrapper** wrapper);
   virtual bool CaptureSnapshotFromBackingStore(BackingStore* backing_store);
   virtual void Observe(int type,
                        const content::NotificationSource& source,