Switch MHTMLGenerationManager to use a Callback.

Relanding:
MHTMLGenerationManager now uses a callback instead of a notification.

BUG=None
TEST=MHTML generation (via extension API should still work).
TBR=jam

Review URL: http://codereview.chromium.org/8674002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@111328 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 17 insertions, 38 deletions

diff --git a/chrome/browser/extensions/extension_save_page_api.cc b/chrome/browser/extensions/extension_save_page_api.cc
index e9c0386..6a8bde6 100644
--- a/chrome/browser/extensions/extension_save_page_api.cc
+++ b/chrome/browser/extensions/extension_save_page_api.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/extensions/extension_save_page_api.h"
 
+#include "base/bind.h"
 #include "base/file_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
@@ -105,46 +106,27 @@ void SavePageAsMHTMLFunction::TemporaryFileCreated(bool success) {
     return;
   }
 
-  registrar_.Add(
-      this, content::NOTIFICATION_MHTML_GENERATED,
-      content::Source<RenderViewHost>(tab_contents->render_view_host()));
-  // TODO(jcivelli): we should listen for navigation in the tab, tab closed,
-  //                 renderer died.
+  MHTMLGenerationManager::GenerateMHTMLCallback callback =
+      base::Bind(&SavePageAsMHTMLFunction::MHTMLGenerated, this);
+
   g_browser_process->mhtml_generation_manager()->GenerateMHTML(
-      tab_contents, mhtml_path_);
+      tab_contents, mhtml_path_, callback);
 }
 
-void SavePageAsMHTMLFunction::Observe(
-    int type,
-    const content::NotificationSource& source,
-    const content::NotificationDetails& details) {
-  DCHECK(type == content::NOTIFICATION_MHTML_GENERATED);
-
-  const MHTMLGenerationManager::NotificationDetails* save_details =
-      content::Details<MHTMLGenerationManager::NotificationDetails>(details).
-          ptr();
-
-  if (mhtml_path_ != save_details->file_path) {
-    // This could happen if there are concurrent MHTML generations going on for
-    // the same tab.
-    LOG(WARNING) << "Received a notification that MHTML was generated but for a"
-        " different file.";
-    return;
-  }
-
-  registrar_.RemoveAll();
-
-  if (save_details->file_size <= 0) {
+void SavePageAsMHTMLFunction::MHTMLGenerated(const FilePath& file_path,
+                                             int64 mhtml_file_size) {
+  DCHECK(mhtml_path_ == file_path);
+  if (mhtml_file_size <= 0) {
     ReturnFailure(kMHTMLGenerationFailedError);
     return;
   }
 
-  if (save_details->file_size > std::numeric_limits<int>::max()) {
+  if (mhtml_file_size > std::numeric_limits<int>::max()) {
     ReturnFailure(kFileTooBigError);
     return;
   }
 
-  ReturnSuccess(save_details->file_size);
+  ReturnSuccess(mhtml_file_size);
 }
 
 void SavePageAsMHTMLFunction::ReturnFailure(const std::string& error) {
diff --git a/chrome/browser/extensions/extension_save_page_api.h b/chrome/browser/extensions/extension_save_page_api.h
index 106cd5a..fc7ce9a 100644
--- a/chrome/browser/extensions/extension_save_page_api.h
+++ b/chrome/browser/extensions/extension_save_page_api.h
@@ -10,12 +10,11 @@
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/extensions/extension_function.h"
 #include "content/browser/tab_contents/tab_contents_observer.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
 #include "webkit/blob/deletable_file_reference.h"
 
-class SavePageAsMHTMLFunction : public AsyncExtensionFunction,
-                                public content::NotificationObserver {
+class FilePath;
+
+class SavePageAsMHTMLFunction : public AsyncExtensionFunction {
  public:
   SavePageAsMHTMLFunction();
 
@@ -31,9 +30,6 @@ class SavePageAsMHTMLFunction : public AsyncExtensionFunction,
  private:
   virtual ~SavePageAsMHTMLFunction();
   virtual bool RunImpl() OVERRIDE;
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
   virtual bool OnMessageReceivedFromRenderView(
       const IPC::Message& message) OVERRIDE;
 
@@ -45,6 +41,9 @@ class SavePageAsMHTMLFunction : public AsyncExtensionFunction,
   void ReturnFailure(const std::string& error);
   void ReturnSuccess(int64 file_size);
 
+  // Callback called once the MHTML generation is done.
+  void MHTMLGenerated(const FilePath& file_path, int64 mhtml_file_size);
+
   // Returns the TabContents we are associated with, NULL if it's been closed.
   TabContents* GetTabContents();
 
@@ -56,8 +55,6 @@ class SavePageAsMHTMLFunction : public AsyncExtensionFunction,
   // The file containing the MHTML.
   scoped_refptr<webkit_blob::DeletableFileReference> mhtml_file_;
 
-  content::NotificationRegistrar registrar_;
-
   DECLARE_EXTENSION_FUNCTION_NAME("experimental.savePage.saveAsMHTML")
 };